Download Number Sense Study Guide

Name:
Unit 1 Number Sense
Study Guide
1.
What is the opposite of -3? ______________________
2.
What is │-22⅝│? _____________________
3.
What is │8│? _____________________
4.
-10 _________ 8
a) >
b) =
c) <
5. -20.4 _______ -20.3
a) >
b) =
c) <
6. If the temperature reading on a thermometer is 5°C, what will the new reading be if the
temperature falls 8.4°C?
7. A submarine is cruising at 40 meters below the surface. It descends 20 meters; then it
rises 35 meters. What is the submarine’s new depth?
8. Which two numbers have 31.5 as their absolute value? _________________
9. Simplify. Show each step.
-6 + {3(-2-5)+[8-(-3)]}
Find the value of each expression. Then say whether your answer is positive,
negative or zero.
10) 4 - 16
11) -6 + (-7)
12) 5(-4)
13) -18 ÷-6
14) (-6)(-9)
15) -2 - (-19)
16) 11 - (-11)
17) -2 + (-21)
18) -21 ÷3
29) 9 + (-3)
20) - 7 - 13
21) 13 - 14
22) 6(-4)(2)
23) (-8)2
24) (-2)3
25) -102
Name:
Unit 1 Number Sense
Study Guide ANSWER KEY
1.
What is the opposite of -3? _________3_____________
2.
What is │-22⅝│? ____22⅝
3.
What is │8│? ________8_____________
4.
-10 ___<______ 8
a) >
b) =
c) <
5. -20.4 __<_____ -20.3
a) >
b) =
c) <
6. If the temperature reading on a thermometer is 5°C, what will the new reading be if the
temperature falls 8.4°C?
5 + (-8.4) = -3.4
So, the new reading would be -3.4°C.
7. A submarine is cruising at 40 meters below the surface. It descends 20 meters; then it
rises 35 meters. What is the submarine’s new depth?
-40 + (-20) + 35
-60 + 35
-25
So, the submarine’s new depth is -25m.
OR
So, the submarine is at 25 meters below sea level.
8. Which two numbers have 31.5 as their absolute value? _31.5 and -31.5________________
9. Simplify. Show each step.
-6 + {3(-2-5)+[8-(-3)]}
-6 + {3(-7) + [8 – (-3)]}
-6 + {3(-7) + (8 + 3)}
-6 + {3(-7) + 11}
-6 – 21 + 11
-27 + 11
-16
Find the value of each expression. Then say whether your answer is positive,
negative or zero.
10) 4 - 16
11) -6 + (-7)
12) 5(-4)
13) -18 ÷-6
4 + (-16) = -12
-13
-20
3
negative
negative
negative
postive
14) (-6)(-9)
15) -2 - (-19)
16) 11 - (-11)
17) -2 + (-21)
45
-2 + (+19) =17
11 + (+11) = 22
-23
positive
positive
positive
negative
18) -21 ÷3
29) 9 + (-3)
20) - 7 - 13
21) 13 - 14
-7
6
-7 + (-13) = - 20
13 + (-14) = -1
negative
positive
negative
negative
22) 6(-4)(2)
(-24)(2) = -48
negative
23) (-8)2
24) (-2)3
25) -102
(-8)(-8) = 64
(-2)(-2)(-2) = -8
The alien spaceship
eats up everything
next to it (-2)
(10)(10) = 100
The alien spaceship
eats up everything
next to it (-8)
positive
negative
The alien spaceship
eats up everything
next to it which is
only the 10.
The negative sign
falls down
so -102= -100
negative