Numeracy
Application of Number
______________
L2
Workbook 3
Ratio
N1/L2.3
basic & keySKILLBUILDER
Number
Ratio
N1/L2.3
Division in a given ratio
Rule
Add the ratios together; e.g. 7:3 = 10, divide the amount by this number to
find one share, then multiply.
e.g. share £250 between Paul and Paula in the ratio 2 : 3
2+3=5
£250  5 = £50
1 share = £50
Paul has 2 shares = 2 × 50 = £100
Paula has 3 shares = 3 × 50 = £150
Check that the shares (£100 + £150) are the same as the amount you started with.
Exercise 1
1.
Share 36 sweets between Bob and Lyn in the ratio 4:5.
2.
Share £84 between Jo and Mel in the ratio 4:3.
3.
A 48 acre field is divided into 2 parts in the ratio 7:5. What size is the smaller part?
4.
X-rays are in the ratio 2:3 for men and women. Out of 1000 X-rays, how many are for
men?
5.
A house builder builds flats and houses in a ratio of 2:5. If he builds 10,360
properties, how many flats is that?
Workbook 3
2
Level 2 Numeracy/Application of Number
 West Nottinghamshire College 2004
basic & keySKILLBUILDER
Number
Ratio
N1/L2.3
Comparing ratios
Rule
Like fractions, ratios must be of the same type before you can compare them
e.g.
Mrs Brown’s evening class has a ratio of men : women of 1 : 3
Mr Green’s evening class has a ratio of men : women of 3 : 4
Which class has the greater ratio of men?
If we multiply the first ratio by 3 we get.
1:33:9
so we are comparing
3 : 9 with 3 : 4
There are 3 men to every 9 women in Mrs Brown’s group, whereas there are 3 men to
every 4 women in Mr Green’s group.
The greater ratio of men is in Mr Green’s group.
6.
The more cement in a mixture, the stronger it is. Which is the stronger of these?
sand : cement
a) 3 : 1
(multiply by 2)
b) 5 : 2
7.
The ratio of men to women at a swimming bath varies. Which has more women,
(a) or (b)?
men : women
a) 1 : 6
b) 2 : 15
8.
(multiply by 2)
Cake mixtures vary; from (a) and (b) below choose the one with more fruit.
fruit : other ingredients
a) 2 : 4
b) 6 : 1
(multiply by 4)
Workbook 3
3
Level 2 Numeracy/Application of Number
 West Nottinghamshire College 2004