The table shows the percentage distribution of population across five age groups for cities A to E.

City	0-13	13-19	19-35	35-60	Above 60
A	18	12	24	30	16
B	16	18	22	29	15
C	20	20	20	25	15
D	15	18	21	26	20
E	18	15	25	24	18

If the populations of the age group 19 to 35 years in city A and city B are 17,280 and 21,120 respectively, then what is the ratio of the total population of city A to that of city B?

A2 : 3

B3 : 4 ✓ Correct

C4 : 5

D5 : 6

Correct answer: (B) 3 : 4

Explanation

The ratio of total populations A to B is 3 to 4, so that is the answer.

In city A the 19 to 35 group is 24 percent, so the total A is 17,280 divided by 0.24.

In city B the 19 to 35 group is 22 percent, so the total B is 21,120 divided by 0.22.

This gives total A as 72,000 and total B as 96,000.

The ratio 72,000 to 96,000 simplifies to 3 to 4.

So the ratio of total populations A to B is 3 to 4.

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