Question

5 boys and 3 girls can do a science projectin 40 days .How long will it take for15 boys and 6girls to do a same project?​

Answer 1

Step-by-step explanation:

Let B and G denote Boys and Girls respectively.

Given 5B = 3G ⇒ 1B = 3/5G.

now 15B + 6G = 15 × 3/5 G + 6G = 9G + 6G = 15G.

If 3 girls can do the project in 40 days then 15 girls can do it in.

3G × 40 ÷ 15G = 3G × 40 × 1/15G = 40/5.

= 8 days.

∴ 15 boys and 6 girls can complete the project in 8 days.