Charts

a) 45

Fail = 15 boys = 1/4 of the pie or 90 degrees

Therefore, if 1/4 = 15, 3/4 = 45

b) Charlie is incorrect because you do not know how many boys and how many girls there are in Year 7. This is required to work out the answer. There may for example be 24 boys and only 5 girls. This would mean 6 boys fail the test and less than 5 girls fail the test. 

a) 8

1. 1. 1. 1. If 64 cars in total, then the following equation will be used to calculate the number of red cars
         2.  ⁶⁴/₁ * ⁴⁵/_360. 
         3. After cross cancellation, this is simplified to:
         4. 64/₁ * ⁵/₄₀
         5. Further cross cancellation:
         6. 8/₁ * ¹/₁

b) 3/8

1. The key here is to remember that the opposite angles when 2 lines cross, create equal angles
2. So given Black and Red are 45º each, this gives 90° in total
3. So remaining in the circle is 360 – 90 = 270
4. Each angle must therefore be 270/2 = 135
5. Every 45 degrees = 1/8th. So 135 = 3/8

a) 2

b) 1

c) 13

1+3+4+2+1+2

a) 30º

1. Yellow + Purple is a right angle so is 90º
2. Therefore, Yellow is 30º

b) 25%

1. 100% for the pie chart. Therefore, Red occupies 1/4 of this.
2. 100/1 * 1/4

c) 90

1. 1. ¹⁸⁰/₃₆₀ * ¹⁸⁰/₁
   2. This is 180 degrees/360 degrees * 180. The equation above can be simplified and you should always do this
   3. ¹/₁ * ⁹⁰/₁

A Molly

B Polly

C Lolly

D Holly

E Dolly

More of a word problem than reading the charts.

a) 1/4

Right angle

b) 50%

Exactly half

c) 24

If 6 chose swimming = 25%, then 100% = 6 x 4 = 24

d) 9

If swimming = 6, gymnastics = 3. Therefore, athletics = 12. 12=3

i) 14C

ii) 9C

On Friday

iii) 7C

18C-11C

B)

i) 8C difference on Thursday

ii) 56/7 = 8C

Total of all temperatures/ number of recorded temperatures

Range is difference between highest and lowest numbers