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Why Mental Math?
• Calculating in you head is a practical life skill.
• Mental math can make written computation
easier or quicker
• Proficiency in mental math contributes to
increased skill in estimation
• Mental calculation can lead to a better
understanding of place value, mathematical
operations, and basic number sense.
• It is new a challenge each day
• Bi-weekly draws
• OUR BRAIN IS WITH US WHEREVER WE
GO, OUR CALCULATOR IS NOT!!
Guidelines for Mental Math
• Mental math is DAILY, but not necessarily a
test daily
• Each test will be 10 questions
• 5 seconds to answer each question
• Test is self corrected, you recorded results
• name goes in for a draw (1, 2, 3 chances)
• If corrected incorrectly no chance to win
during the next draw.
• If no red pen, no tickets for that day
• Unprepared for three classes eliminates you
from that weeks draw.
• Strategies used will be discussed
Mental Math # 1
1)
2)
3)
4)
5)
6)
7)
8)
The operation associated with the term addend is ?
The operation associated with the term quotient is ?
The operation associated with the term factor is ?
The operation associated with the term dividend is ?
The operation associated with the term product is ?
The operation associated with the term minuend is ?
The operation associated with the term sum is ?
The operation associated with the term subtrahend
is ?
9) The operation associated with the term is divisor?
10) The operation associated with the term is
difference ?
Mental Math # 1
1)
The operation associated with the term addend is +
2)
3)
The operation associated with the term quotient is 
The operation associated with the term factor is x
4)
5)
6)
7)
8)
The operation associated with the term dividend is 
The operation associated with the term product is x
The operation associated with the term minuend is The operation associated with the term sum is +
The operation associated with the term subtrahend
is -
9) The operation associated with the term is divisor 
10) The operation associated with the term is
difference -
Mental Math # 2
1) 70 + 43 = 113
2) 10 + 70 + 3 = 83
3) 200 - 50 = 150
4) 50 – 10 = 40
5) 500 - 200 = 300
6) 4 x 4 = 16
7) 4 x 300 = 1200
8) 50  10 = 5
9) 8  4 = 2
10) 40  1 = 40
Name the
term
represented
by the
number that
is blue.
Mental Math # 2
1) 70 + 43 (addend) = 113
2) 10 + 70 + 3 = 83 (sum)
3) 200 (minuend) - 50 = 150
4) 50 – 10 = 40 (difference)
5) 500 - 200 (subtrahend) = 300
6) 4 (factor) x 4 = 16
7) 4 x 300 = 120 (product)
8) 50  10 = 5 (quotient)
9) 8  4 (divisor) = 2
10) 40 (dividend)  1 = 40
Mental Math # 3
1) 70 x 40 = 2800
2) 500 + 43 = 543
3) 20  5 = 4
4) 20 x 50 = 1000
5) 700 – 300 = 400
6) 50 + 50 = 100
7) 30  2 = 15
8) 50 - 10 = 40
9) 8  4 = 2
10) 100 - 40 = 60
Name the
term
represented
by the
number that
is blue.
Mental Math # 3
1) 70 x 40 (factor) = 2800
2) 500 + 43 = 543 (sum)
3) 20 (dividend)  5 = 4
4) 20 (factor) x 50 = 1000
5) 700 (minuend) – 300 = 400
6) 50 (addend) + 50 = 100
7) 30  2 (divisor) = 15
8) 50 - 10 = 40 (difference)
9) 8  4 = 2 (quotient)
10) 100 - 40 (subtrahend) = 60
1)
2)
Mental Math # 4
When you multiply 2 numbers, the result is called the ?
The numbers you add together to get a result are called
the ?
3) How many you take away from the amount you started
with is called the ?
4) The amount you start with when dividing is called the ?
5) The result of dividing 2 numbers is called the ?
6) To find a product, the numbers you multiply are called ?
7) The result of 2 numbers added together is called the ?
8) The number of equal groups you want to make when
dividing is called the ?
9) The amount you get when subtracting two numbers is
called the ?
10) The amount you start with when subtracting is called
the ?
1)
Mental Math # 4
When you multiply 2 numbers, the result is called the
product.
2) The numbers you add together to get a result are called
the addends.
3) How many you take away from the amount you started with
is called the subtrahend.
4) The amount you start with when dividing is called the
dividend.
5) The result of dividing 2 numbers is called the quotient.
6) To find a product, the numbers you multiply are called
factors.
7) The result of 2 numbers added together is called the sum.
8) The number of equal groups you want to make when dividing
is called the divisor.
9) The amount you get when subtracting two numbers is called
the difference.
10) The amount you start with when subtracting is called the
minuend.
Mental Math # 5
1) The product of 5 and 2 is ?
2) The sum of 5 and 2 is ?
3) The factors are 3 and 5; the result is ?
4) The difference of 10 and 8 is ?
5) 4 x 100 + 8 x 1 + 5 x 1000 =
6) 50 000 + 3000 + 20 + 7 =
7) 500 + 300 + 40 =
8) 80 + 40 + 20 + 2 =
9) 4000 + 500 + 3000 + 20 =
10) The quotient is 5, the divisor is 6 what
is the dividend?
Mental Math # 5
1) The product of 5 and 2 is ? 10
2) The sum of 5 and 2 is ? 7
3) The factors are 3 and 5; the result is? 15
4) The difference of 10 and 8 is ? 2
5) 4 x 100 + 8 x 1 + 5 x 1000 = 5408
6) 50 000 + 3000 + 20 + 7 = 53 027
7) 500 + 300 + 40 = 840
8) 80 + 40 + 20 + 2 = 142
9) 4000 + 500 + 3000 + 20 = 7520
10) The quotient is 5, the divisor is 6 what is
the dividend? 30
Mental Math # 6
1) 7000 + 300 + 40 + 3 =
2) 9000 + 70 + 3 =
3) 2000 + 50 + 400 + 4 =
4) 50 + 4000 + 7 + 300 =
5) 5 x 1000 + 3 x 100 + 9 x 10 + 2 x 1 =
6) 4 x 100 + 8 x 1 + 5 x 1000 =
7) 50 000 + 3000 + 20 + 7 =
8) 500 + 300 + 40 =
9) 80 + 40 + 20 + 2 =
10) 4000 + 500 + 3000 + 20 =
1)
2)
3)
4)
5)
Mental Math # 6
7000 + 300 + 40 + 3 = 7343
9000 + 70 + 3 = 9073
2000 + 50 + 400 + 4 = 2454
50 + 4000 + 7 + 300 = 4357
5 x 1000 + 3 x 100 + 9 x 10 + 2 x 1 =
5392
6) 4 x 100 + 8 x 1 + 5 x 1000 = 5408
7) 50 000 + 3000 + 20 + 7 = 53 027
8) 500 + 300 + 40 = 840
9) 80 + 40 + 20 + 2 = 142
10) 4000 + 500 + 3000 + 20 = 7520
1)
2)
3)
4)
5)
Mental Math # 7
500 + 3000 + 70 + 3 =
6000 + 700 + 3
2000 + 500 + 40 + 4 =
50 000 + 30 + 7 + 8000 =
3 x 10 000 + 1 x 1000 + 9 x 100 + 2 x
10 + 3 x 1 =
6) 4 x 1000 + 2 x 1 + 5 x 100 =
7) 200 + 300 + 20 + 5 =
8) 500 + 500 + 400 + 24 =
9) 40 + 60 + 20 + 70 + 30 =
10) 4200 + 500 + 60 =
1)
2)
3)
4)
5)
Mental Math # 7
500 + 3000 + 70 + 3 = 3573
6000 + 700 + 3 = 6703
2000 + 500 + 40 + 4 = 2544
50 000 + 30 + 7 + 8000 = 58 037
3 x 10 000 + 1 x 1000 + 9 x 100 + 2 x
10 + 3 x 1 = 31 923
6) 4 x 1000 + 2 x 1 + 5 x 100 = 4502
7) 200 + 300 + 20 + 5 = 525
8) 500 + 500 + 400 + 24 = 1424
9) 40 + 60 + 20 + 70 + 30 = 220
10) 4200 + 500 + 60 = 4760
Mental Math # 8
1) 90 + 7000 + 500 + 6 =
2) 60 000 + 400 + 20 + 3 =
3) 300 + 700 + 80 + 4 =
4) 50 000 + 30 + 7 + 8000 =
5) 3 x 1000 + 9 x 100 + 6 x 10 + 2 x 1 =
6) 4 x 1000 + 2 x 10 000 + 8 x 100 =
7) 20 + 80 + 30 + 5 + 70 =
8) 900 + 600 + 400 + 72 + 100 =
9) 2000 + 8000 + 700 + 30 =
10) 5100 + 900 + 70 =
Mental Math # 8
1) 90 + 7000 + 500 + 6 = 7596
2) 60 000 + 400 + 20 + 3 = 60 423
3) 300 + 700 + 80 + 4 = 1084
4) 50 000 + 30 + 7 + 8000 = 58 037
5) 3 x 1000 + 9 x 100 + 6 x 10 + 2 x 1 = 3962
6) 4 x 1000 + 2 x 10 000 + 8 x 100 = 24 800
7) 20 + 80 + 30 + 5 + 70 = 205
8) 900 + 600 + 400 + 72 + 100 = 2072
9) 2000 + 8000 + 700 + 30 = 10 730
10) 5100 + 900 + 70 = 6070
Mental Math # 9
1) 20 + 6000 + 400 + 7 =
2) 50 000 + 9000 + 200 + 30 =
3) 400 + 600 + 3 + 40 =
4) 20 000 + 300 + 9 + 4000 =
5) 5 x 1000 + 3 x 100 + 7 x 10 + 2 x 1 =
6) 7 x 1000 + 8 x 10 000 + 6 x 100 =
7) 50 + 90 + 50 + 5 + 10 =
8) 300 + 600 + 700 + 42 =
9) 4000 + 500 + 500 + 33 =
10) 3700 + 300 + 76 =
1)
2)
3)
4)
5)
Mental Math # 9
20 + 6000 + 400 + 7 = 6427
50 000 + 9000 + 200 + 30 = 59 230
400 + 600 + 3 + 40 = 1043
20 000 + 300 + 9 + 4000 = 24 309
5 x 1000 + 3 x 100 + 7 x 10 + 2 x 1 =
5372
6) 7 x 1000 + 8 x 10 000 + 6 x 100 =
87 600
7) 50 + 90 + 50 + 5 + 10 = 205
8) 300 + 600 + 700 + 42 = 1642
9) 4000 + 500 + 500 + 33 = 5033
10) 3700 + 300 + 76 = 4076
Mental Math # 10
1) 8 x 8 =
2) 5 x 9=
3) 4 x 6 =
4) 20 divided by 5 =
5) 3 x 7 =
6) 72 divided by 9 =
7) 7 x 8 =
8) 30 divided by 6 =
9) 7 x 7 =
10) 60 divided by 6 =
Mental Math # 10
1) 8 x 8 = 64
2) 5 x 9= 45
3) 4 x 6 = 24
4) 20 divided by 5 = 4
5) 3 x 7 = 21
6) 72 divided by 9 = 8
7) 7 x 8 = 56
8) 30 divided by 6 = 5
9) 7 x 7 = 49
10) 60 divided by 6 = 10
Mental Math # 11
1) 4 x 8 =
2) 3 x 9=
3) 7 x 5 =
4) 36 divided by 6 =
5) 9 x 9 =
6) 56 divided by 7 =
7) 2 x 8 =
8) 55 divided by 5 =
9) 7 x 6 =
10) 64 divided by 8 =
Mental Math # 11
1) 4 x 8 = 32
2) 3 x 9= 27
3) 7 x 5 = 35
4) 36 divided by 6 = 6
5) 9 x 9 = 81
6) 56 divided by 7 = 8
7) 2 x 8 = 16
8) 55 divided by 5 = 11
9) 7 x 6 = 42
10) 64 divided by 8 = 8
Mental Math # 12
1) 4 x 3 =
2) 6 x 8=
3) 8 x 5 =
4) 63 divided by 9 =
5) 4 x 7 =
6) 32 divided by 4 =
7) 2 x 12 =
8) 72 divided by 8 =
9) 7 x 7 =
10) 48 divided by 8 =
Mental Math # 12
1) 4 x 3 = 12
2) 6 x 8= 48
3) 8 x 5 = 40
4) 63 divided by 9 = 7
5) 4 x 7 = 28
6) 32 divided by 4 = 8
7) 2 x 12 = 24
8) 72 divided by 8 = 9
9) 7 x 7 = 49
10) 48 divided by 8 = 6
Mental Math # 13
1) 8 x 3 =
2) 9 x 8=
3) 9 x 6 =
4) 36 divided by 9 =
5) 4 x 4 =
6) 40 divided by 5 =
7) 3 x 12 =
8) 42 divided by 6 =
9) 7 x 4 =
10) 64 divided by 8 =
Mental Math # 13
1) 8 x 3 = 24
2) 9 x 8= 72
3) 9 x 6 = 54
4) 36 divided by 9 = 4
5) 4 x 4 = 16
6) 40 divided by 5 = 8
7) 3 x 12 = 36
8) 42 divided by 6 = 7
9) 7 x 4 = 28
10) 64 divided by 8 = 8
Mental Math # 14
1) 200 + 60 000 + 4 + 70 =
2) 50 + 80 + 90 + 20 + 10 =
3) 400 + 600 + 3000 + 400 =
4) 23 + 300 + 7 =
5) 6 x 1000 + 2 x 100 + 0 x 10 + 2 x 1 =
6) 9 x 1000 + 8 x 10 000 + 6 x 100 + 4 x 10 =
7) 9 + 7 =
8) 90 + 70 =
9) 139 + 7 =
10) 390 + 70 =
1)
2)
3)
4)
5)
6)
Mental Math # 14
200 + 60 000 + 4 + 70 = 60 274
50 + 80 + 90 + 20 + 10 = 250
400 + 600 + 3000 + 400 = 4400
23 + 300 + 7 = 330
6 x 1000 + 2 x 100 + 0 x 10 + 2 x 1 = 6202
9 x 1000 + 8 x 10 000 + 6 x 100 + 4 x 10 =
89 640
7) 9 + 7 = 16
8) 90 + 70 = 160
9) 139 + 7 = 146
10) 390 + 70 = 460
Mental Math # 15
1) 500 + 20 + 500 + 80 =
2) 30 + 80 + 70 + 10 + 10 =
3) 200 + 800 + 30 + 400 =
4) 51 + 3000 + 9 =
5) 8 x 1000 + 3 x 100 + 4 x 10 + 4 x 1 =
6) 9 x 10 000 + 8 x 1 + 6 x 1000 =
7) 7 + 5 =
8) 70 + 50 =
9) 127 + 5 =
10) 330 + 37 =
1)
2)
3)
4)
5)
Mental Math # 15
500 + 20 + 500 + 80 = 1100
30 + 80 + 70 + 10 + 10 = 200
200 + 800 + 30 + 400 = 1430
51 + 3000 + 9 = 3060
8 x 1000 + 3 x 100 + 4 x 10 + 4 x 1 =
8344
6) 9 x 10 000 + 8 x 1 + 6 x 1000 = 96 008
7) 7 + 5 = 12
8) 70 + 50 = 120
9) 127 + 5 = 132
10) 330 + 37 = 367
Mental Math # 16
1) 48 + 21 =
2) 53 + 34 =
3) 34 + 52 =
4) 456 + 120 =
5) 438 + 340 =
6) 629 + 310 =
7) 400 + 231 =
8) 456 + 42 =
9) 381 + 405 =
10) 705 + 220 =
Mental Math # 16
1) 48 + 21 = 69
2) 53 + 34 = 87
3) 34 + 52 = 86
4) 456 + 120 = 576
5) 438 + 340 = 778
6) 629 + 310 = 939
7) 400 + 231 = 631
8) 456 + 42 = 498
9) 381 + 405 = 786
10) 705 + 220 = 925
Mental Math # 17
1) 430 + 53 =
2) 510 + 87 =
3) 349 + 220 =
4) 456 + 440 =
5) 352 + 527 =
6) 600 + 350 =
7) 434 + 231 =
8) 156 + 420 =
9) 321 + 45 =
10) 615 + 224 =
Mental Math # 17
1) 430 + 53 = 483
2) 510 + 87 = 597
3) 349 + 220 = 569
4) 456 + 440 = 896
5) 352 + 527 = 879
6) 600 + 350 = 950
7) 434 + 231 = 665
8) 156 + 420 = 576
9) 321 + 45 = 366
10) 615 + 224 = 839
Mental Math # 18
1) 974 + 23 =
2) 320 + 29 =
3) 341 + 208 =
4) 677 + 320 =
5) 425 + 563 =
6) 60 + 322 =
7) 400 + 231 =
8) 424 + 424 =
9) 333 + 425 =
10) 610 + 220 =
Mental Math # 18
1) 974 + 23 = 997
2) 320 + 29 = 349
3) 341 + 208 = 549
4) 677 + 320 = 997
5) 425 + 563 = 988
6) 60 + 322 = 382
7) 400 + 231 = 631
8) 424 + 424 = 848
9) 333 + 425 = 758
10) 610 + 220 = 830
Mental Math # 19
1) 543 + 253 =
2) 841 + 200 =
3) 128 + 331 =
4) 415 + 363 =
5) 52 + 315 =
6) 400 + 200 + 387 =
7) 398 + 502 =
8) 260 + 540 =
9) 390 + 208 =
10) 111 + 111 + 111 =
Mental Math # 19
1) 543 + 253 = 796
2) 841 + 200 = 1041
3) 128 + 331 = 459
4) 415 + 363 = 778
5) 52 + 315 = 367
6) 400 + 200 + 387 = 987
7) 398 + 502 = 900
8) 260 + 540 = 800
9) 390 + 208 = 598
10) 111 + 111 + 111 = 333
Mental Math # 20
1) Five and three tenths =
2) Thirty two and four hundredths =
3) Seventy-seven thousandths =
4) Two hundred four and five hundredths =
5) Nine hundredths =
6) 4 + 0.2 =
7) 30 + 5 + 0.9 + 0.07 =
8) 200 + 0.8 =
9) (5 x 1) + (2 x 0.1) + (4 x 0.01) =
10) 3 x 100 + 6 x 0.01 =
Mental Math # 20
1) Five and three tenths = 5.3
2) Thirty two and four hundredths =
32.04
3) Seventy-seven thousandths = 0.077
4) Two hundred four and five hundredths
= 204.05
5) Nine hundredths = 0.09
6) 4 + 0.2 = 4.2
7) 30 + 5 + 0.9 + 0.07 = 35.97
8) 200 + 0.8 = 200.8
9) (5 x 1) + (2 x 0.1) + (4 x 0.01) = 5.24
10) 3 x 100 + 6 x 0.01 = 300.06
1)
2)
3)
4)
Mental Math # 21
Nine and three hundredths =
Thirty two and four tenths =
Seven thousandths =
Three hundred and fifteen
thousandths =
5) Nine hundredths =
6) 5 + 0.2 + 0.06 =
7) 300 + 50 + 0.9 + 0.04 =
8) 20 + 0.08 + 3 =
9) (5 x 0.001) + (2 x 0.01) + (4 x 0.1) =
10) 3 x 100 + 6 x 0.1 + 4 x 1 =
1)
2)
3)
4)
Mental Math # 21
Nine and three hundredths = 9.03
Thirty two and four tenths = 32.4
Seven thousandths = 0.007
Three hundred and fifteen
thousandths = 300.015
5) Nine hundredths = 0.09
6) 5 + 0.2 + 0.06 = 5.26
7) 300 + 50 + 0.9 + 0.04 = 350.94
8) 20 + 0.08 + 3 = 23.08
9) (5 x 0.001) + (2 x 0.01) + (4 x 0.1) =
0.425
10) 3 x 100 + 6 x 0.1 + 4 x 1 = 304.6
1)
One Whole
Mental Math # 22
2)
3)
4)
5)
6)
7)
8)
9)
10)
1)
Mental Math # 22
One and
four tenths or 1.4
2)
Fifty-three
hundredths or
0.53
3)
One and three
hundredths or
1.03
4)
One and
Two tenths or 1.2
5)
One and thirtyfour
thousandths or
1. 034
6)
Five thousandths
or 0.005
7)
One and thirteen
thousandths or
1.013
8)
Two and one
hundred fortytwo thousandths
or 2.142
9)
Twenty-two
thousandths or
0.022
10)
One and five
hundredths or
1.05
One Whole
1)
2)
3)
4)
5)
Mental Math # 23
One Whole
6)
7)
8)
9)
10)
Mental Math # 23
Mental Math # 23
1)
2)
3)
4)
5)
1.134
2.016
1.308
2.153
4.231
Mental Math # 23
6)
1.109
2.221
7)
8)
9)
10)
1.006
0.342
4.03
One Whole
1)
2)
3)
4)
5)
Mental Math # 24
One Whole
6)
7)
8)
9)
10)
Mental Math # 24
One Whole
1)
2)
3)
4)
5)
Mental Math # 24
1.13
10.37
5.04
21.33
33.61
One Whole
Mental Math # 24
1.2
6)
10.5
7)
3.32
8)
9)
10)
1.03
15.3
One Whole
1)
2)
3)
4)
5)
Mental Math # 25
One Whole
6)
7)
8)
9)
10)
Mental Math # 25
One Whole
Mental Math # 25
1)
2.05
2)
0.72
13.06
3)
4)
5)
0.4
30.04
One Whole
6)
7)
8)
9)
10)
Mental Math # 25
1.27
0.42
2.5
1.13
13.01
Mental Math # 26
1) 3.25 or 3.5
2) 2.000 or 2.001
3) 0.98 or 0.89 =
4) 98.9 or 98.19
5) 10.01 or 10.010 =
6) 6.6 or 6.60
7) Two hundredths or two thousandths =
8) 1.9 or 0.999
9) 1 or 0.95 =
10) 636 or 663 =
Mental Math # 26
1) 3.25 or 3.5
2) 2.000 or 2.001
3) 0.98 or 0.89
4) 98.9 or 98.19
5) 10.01 or 10.010
6) 6.6 or 6.60
7) Two hundredths or two thousandths
8) 1.9 or 0.999
9) 1 or 0.95
10) 636 or 663
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
Mental Math # 27
3.25 rounded to the nearest tenth =
234.9 rounded to the nearest whole number =
1.984 rounded to the nearest hundredth =
48.9 rounded to the nearest ten =
10.08 rounded to the nearest tenth =
6.6 rounded to the nearest whole number =
1465.9 rounded to the nearest hundred =
7.3 rounded to the nearest whole number =
0.6544 rounded to the nearest thousandths =
1.95 rounded to the nearest tenth =
1)
2)
3)
4)
5)
6)
7)
8)
9)
Mental Math # 27
3.25 rounded to the nearest tenth = 3.3
234.9 rounded to the nearest whole number = 235
1.984 rounded to the nearest hundredth = 1.98
48.9 rounded to the nearest ten = 50
10.08 rounded to the nearest tenth = 10.1
6.6 rounded to the nearest whole number = 7
1465.9 rounded to the nearest hundred = 1500
7.3 rounded to the nearest whole number = 7
0.6544 rounded to the nearest thousandths =
0.654
10) 1.95 rounded to the nearest tenth = 2
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
Mental Math # 28
9.252 rounded to the nearest hundredth =
2399 rounded to the nearest thousand =
5.984 rounded to the nearest tenth =
48.55 rounded to the nearest tenth =
10.087 rounded to the nearest hundredth =
8.8 rounded to the nearest whole number =
7535.9 rounded to the nearest hundred =
7.22 rounded to the nearest whole number =
0.9999 rounded to the nearest thousandths =
33.91 rounded to the nearest tenth =
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
Mental Math # 28
9.252 rounded to the nearest hundredth = 9.25
2399 rounded to the nearest thousand = 2000
5.984 rounded to the nearest tenth = 6
48.55 rounded to the nearest tenth = 48.6
10.087 rounded to the nearest hundredth = 10.09
8.8 rounded to the nearest whole number = 9
7535.9 rounded to the nearest hundred = 7500
7.22 rounded to the nearest whole number = 7
0.9999 rounded to the nearest thousandths = 1
33.91 rounded to the nearest tenth = 33.9
Mental Math # 29
1) 50 x 30 =
2) 80 x 3 =
3) 20 x 20 =
4) 40 x 80 =
5) 300 x 3 =
6) 60 x 500 =
7) 800 x 50 =
8) 900 x 20 =
9) 60 x 90 =
10) 40 x 300 =
Mental Math # 29
1) 50 x 30 = 1500
2) 80 x 3 = 240
3) 20 x 20 = 400
4) 40 x 80 = 3200
5) 300 x 3 = 900
6) 60 x 500 = 30 000
7) 800 x 50 = 40 000
8) 900 x 20 = 18 000
9) 60 x 90 = 5400
10) 40 x 300 = 12 000
Mental Math # 30
1) 10 x 30 =
2) 3 x 500 =
3) 2.4 x 2 =
4) 5 x 80 =
5) 100 x 38 =
6) 6.2 x 2 =
7) 90 x 50 =
8) 300 x 20 =
9) 10 x 96 =
10) 1.25 x 3 =
Mental Math # 30
1) 10 x 30 = 300
2) 3 x 500 = 1500
3) 2.4 x 2 = 4.8
4) 5 x 80 = 400
5) 100 x 38 = 3800
6) 6.2 x 2 = 12.4
7) 90 x 50 = 4500
8) 300 x 20 = 6000
9) 10 x 96 = 960
10) 1.25 x 3 = 3.75
Mental Math # 31
1) 100 x 93 =
2) 30 x 70 =
3) 0.9 x 2 =
4) 50 x 60 =
5) 1 x 3.8 =
6) 10 x 3.8 =
7) 200 x 50 =
8) 30 x 40 =
9) 10 x 180 =
10) 1.99 x 2 =
Mental Math # 31
1) 100 x 93 = 9300
2) 30 x 70 = 2100
3) 0.9 x 2 = 1.8
4) 50 x 60 = 3000
5) 1 x 3.8 = 3.8
6) 10 x 3.8 = 38
7) 200 x 50 = 10 000
8) 30 x 40 = 1200
9) 10 x 180 = 1800
10) 1.99 x 2 = 3.98
Mental Math # 32
* denotes an estimate
1) 30 x 90 =
2) 5 x $9.13 = *
3) 3 x $7.97 = *
4) 7 x $2.06 = *
5) $5.13 x 6 = *
6) 5 x $3.89 = *
7) 10 x 3.8 =
8) 300 x 50 =
9) 10 x 340 =
10) $1.98 x 2 = *
Mental Math # 32
1) 30 x 90 = 2700
2) 5 x $9.13 = $45
3) 3 x $7.97 = $24
4) 7 x $2.06 = $14 or 14.42
5) $5.13 x 6 = $30
6) 5 x 3.89 = $20
7) 10 x 3.8 = $38
8) 300 x 50 = 15 000
9) 10 x 340 = 3400
10) $1.98 x 2 = $3.96 or $4.00
Mental Math # 33
* denotes an estimate
1) 20 x 700 =
2) 9 x $4.21 = *
3) 9 x $0.97 = *
4) 5 x $3.36 = *
5) $5.13 x 6 = *
6) 5 x 3.09 = *
7) 1 x 5.9 =
8) 10 x 5.9 =
9) 100 x 66 =
10) $1.05 x 3 =
Mental Math # 33
1) 20 x 700 = 14 000
2) 9 x $4.21 = $36
3) 9 x $0.97 = $9
4) 5 x $3.36 = $15
5) $5.13 x 6 = $30
6) 5 x 3.09 = $15 or 15.45
7) 1 x 5.9 = 5.9
8) 10 x 5.9 = 59
9) 100 x 66 = 6600
10) $1.05 x 3 = $3.15 or $3.00
Mental Math # 34
1) 4 x 45 =
2) 97 x 2 =
3) 6 x 55 =
4) 5 x 36 =
5) 4 x 622 =
6) 34 x 3 =
7) 20 x 18 =
8) 7 x 56 =
9) 66 x 3 =
10) 52 x 7 =
Mental Math # 34
1) 4 x 45 = 180
2) 97 x 2 = 194
3) 6 x 55 = 330
4) 5 x 36 = 180
5) 4 x 622 = 2488
6) 34 x 3 = 102
7) 20 x 18 = 360
8) 7 x 56 = 392
9) 66 x 3 = 198
10) 52 x 7 = 364
Mental Math # 35
1) 45 x 5 =
2) 76 x 3 =
3) 61 x 5 =
4) 54 x 3 =
5) 4 x 62 =
6) 43 x 4 =
7) 3 x 91 =
8) 4 x 65 =
9) 9 x 32 =
10) 5 x 73 =
Mental Math # 35
1) 45 x 5 = 225
2) 76 x 3 = 228
3) 61 x 5 = 305
4) 54 x 3 = 162
5) 4 x 62 = 248
6) 43 x 4 = 172
7) 3 x 91 = 273
8) 4 x 65 = 260
9) 9 x 32 = 288
10) 5 x 73 = 365
Mental Math # 36
1) 55 x 4 =
2) 92 x 5 =
3) 71 x 7 =
4) 4 x 71 =
5) 9 x 63 =
6) 20 x 49 =
7) 30 x 51 =
8) 3 x 77 =
9) 6 x 35 =
10) 63 x 7 =
Mental Math # 36
1) 55 x 4 = 220
2) 92 x 5 = 460
3) 71 x 7 = 497
4) 4 x 71 = 284
5) 9 x 63 = 567
6) 20 x 49 = 980
7) 30 x 51 = 1530
8) 3 x 77 = 231
9) 6 x 35 = 210
10) 63 x 7 = 441
Mental Math # 37
1) 10 x 7.5 =
2) 0.9 x 10 =
3) 100 x 0.97 =
4) 10 x 3.36 =
5) 5.13 x 100 =
6) 100 x 30.9 =
7) 10 x 0.018 =
8) 1000 x 5.9 =
9) 6.6  10 =
10) 1.05 x 10 =
Mental Math # 37
1) 10 x 7.5 = 75
2) 0.9 x 10 = 9
3) 100 x 0.97 = 97
4) 10 x 3.36 = 33.6
5) 5.13 x 100 = 513
6) 100 x 30.9 = 3090
7) 10 x 0.018 = 0.18
8) 1000 x 5.9 = 5900
9) 6.6  10 = 0.66
10) 1.05 x 10 = 10.5
Mental Math # 38
1) 100 x 39.1 =
2) 9.3 x 10 =
3) 10 x 0.93 =
4) 100 x 6.3 =
5) 3.4  10 =
6) 5.13 x 10 =
7) 10 x 30.9 =
8) 10 x 0.001 =
9) 1000 x 0.5 =
10)10.5  100 =
Mental Math # 38
1) 100 x 39.1 = 3910
2) 9.3 x 10 = 93
3) 10 x 0.93 = 9.3
4) 100 x 6.3 = 630
5) 3.4  10 = 0.34
6) 5.13 x 10 = 51.3
7) 10 x 30.9 = 309
8) 10 x 0.001 = 0.01
9) 1000 x 0.5 = 500
10)10.5  100 = 0.105
Mental Math # 39
1) 45.1  10 =
2) 9.3  10 =
3) 67  10 =
4) 6.3  100 =
5) 3400  100 =
6) 51.3  10 =
7) 10 x 39.1 =
8) 413.1  100 =
9) 2.5  1000 =
10)750.5  100 =
Mental Math # 39
1) 45.1  10 = 4.51
2) 9.3  10 = 0.93
3) 67  10 = 6.7
4) 6.3  100 = 0.063
5) 3400  100 = 34
6) 51.3  10 = 5.13
7) 10 x 39.1 = 391
8) 413.1  100 =4.131
9) 2.5  1000 = 0.0025
10)750.5  100 = 7.505
Mental Math # 40
1) 83  100 =
2) 4.7 x 10 =
3) 69.2  10 =
4) 16.3  100 =
5) 30.4  10 =
6) 933  10 =
7) 10 x 92.1 =
8) 4  1000 =
9) 2.5  100 =
10)5.2  10 =
Mental Math # 40
1) 83  100 = 0.83
2) 4.7 x 10 = 47
3) 69.2  10 = 6.92
4) 16.3  100 = 0.163
5) 30.4  10 = 3.04
6) 933  10 = 93.3
7) 10 x 92.1 = 921
8) 4  1000 =0.004
9) 2.5  100 = 0.025
10)5.2  10 = 0.52