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.