help

[thick herald]

@haughty crystal

[haughty crystal]

Yeah

[thick herald]

So, the ratio of the numbers of people who like pop to who like rap is 5 : 2.

Using the Venn diagram we can see that the people who like pop is 28 + x. We can also see that the people who like rap is x + 1. This therefore let's you equate two ratios;

28 + x : x + 1 = 5 : 2

, turn them into fractions

Giving you 28 + x / x + 1 = 5 / 2

Cross multiply, giving you
2 ( 28 + x ) = 5 (x + 1 )

Expanding and simplifying gives you x = 17.

So the total number of students in the survey is therefore 28 + 17 + 1 + 13 = 59

[haughty crystal]

If got the total as 49 by saying that the ratio is equal to 5x:2x since the total is X