280 mangoes are divided among some boys and girls, 50 in all, so that each boy gets 5 mangoes and each girl gets 7 mangoes. How many girls are there?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 15
If all 50 children were boys, they would get 5 mangoes each. Each girl takes 2 mangoes more than a boy, so the extra mangoes count the girls.
Mangoes if all were boys \(=50\times5=250\)
Extra mangoes \(=280-250=30\)
Girls \(=30\div2=15\)
Check: 35 boys \(\times\,5+15\) girls \(\times\,7=175+105=280\)
There are 15 girls.