Questions I Got Wrong

Question 1

One fifth of pupils are year 7
The ratio of boys to girls in year 7 is 3:2
20% of the girls in year 7 have blonde hair
What fraction of pupils in the school are girls in year 7 with blonde hair?

Answer 1

3/5 are year 7 and girls
1/5x 3/5 = 3/25 are year 7 blonde girls
3/25 x 1/5 =
3/125 pupils in the school are year 7 girls with blonde hair

Question 2

Is 3/125 a recurring or terminating decimal?

Answer 2

Terminating decimals have denominators with prime factors of 2 and 5 only so 3/125 is a terminating decimals

Question 3

Work out the values of a and b

a/11 + b/6 = 25/33

Answer 3

Make both denominators 66
Use trial and error

A= 1
B=4

Question 4

X and y are integers and 0

Answer 4

X=2 y= 15
X=4 y= 12
X=6 y=9

Question 5

Give two examples of irrational numbers

Answer 5

Surds and pie

Question 6

Eric says
‘even square numbers always have more factors the old square numbers’
Prove Eric is wrong

Answer 6

Show any even has less factors than odd for example
4= 1,2,4
81=1,9,27,81

Question 7

X is a common multiple of six and seven and a common factor of 252 and 420
Given that 50

Answer 7

X=84