To solve the given problem
We can consider,
30% are girls of 30 people
70% are boys in 30 people
In order to get the number, we just multiply the total number
of people with the percentage of the designated target populace.
1. 30 x 0.3 =
9 girls
2. 30 x 0.7 =
21 boys
3. 21 boys + 9
girls = 30 people
Hence, there are 21 boys.