In a fund-raising committee of 45 people, the ratio of men to women is 7 : 2. Find the number of women required to join the existing committee so that the ratio of men to

women is changed to 5:4

18 women

Step-by-step explanation:

Sum the parts of the ratio, 7 + 2 = 9 parts

Divide 45 by 9 to find the value of one part of the ratio.

45 : 9 = 5 ← value of 1 part, thus

7 parts = 7 * 5 = 35 ← number of men

2 parts = 2 * 5 = 10 ← number of women

We require to change the ratio to 5 : 4

The 5 part of the ratio represents the number of men, thus

35 : 5 = 7 ← value of 1 part of the ratio, thus

4 * 7 = 28 ← number of women

Number of women required to join existing committee = 28 - 10 = 18