Answer:
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