Download Week 2 Maths Revision

Week 2 Maths Revision
Factor : a whole number that divides exactly into another number.
example 3 is a factor of 9. 4 and 5 are both factors of 20.
For
Common Factor : numbers that have the same factors are called ‘common
factors’. For example : 2 is a common factor of 4, 8 and 14. 8 is a common
factor of 24 and 40. To find common factors you need to list the factors for
each number and find the factors that are in each list.
Multiple : a multiple is a number made by multiplying two whole numbers
greater than 1. For example 12 is a multiple of 6 as 2 x 6 = 12. 24 is a
multiple of 8 because 8 x 3 = 24.
Common multiple : a multiple that is shared by 2 or more numbers. For
example: 12 is a common multiple of 2, 3, 4 and 6. To find common multiples
you need to list the multiples of each number and find the numbers that are in
each list.
Equivalent fractions
¼
0.25
25%
½
0.5
50%
¾
0.75
75%
1 whole
1.0
100%
1/
5
0.2
20%
1/
10
0.1
10%
To find 10% or 1/10 of a number you need to divide the number by 10.
To find 5% of a number you can find 10% and then halve the answer.
For example : to find 15% of £240 you would first find 10% and then find 5%.
10% of £240 = £24.
5% of £240 = £12
15% of £240 = £24 + £12 = £36.
Statistics
Mean : this is the same as the ‘average’. To calculate the mean of a set of
numbers you must add the numbers and then divide by how many amounts
there were.
For example :
Day
Temp
Mon
60
Tues
80
Wed
70
Thurs
100
Fri
90
Sat
80
Sun
80
To find the average temperature you need to add each temperature and then
divide by 7 (as there are 7 amounts). 6 + 8 + 7 + 10 + 9 + 8 + 8 = 56
56 ÷ 7 = 8
The mean (or average) temperature is 80.
Mode : is the most common number. (80)
Median : is the middle number : put all the numbers in ascending order and
find the middle one.
6, 7, 8, 8, 8, 8, 9, 10. Median is 80.