A girl can put up 1 tent in 5 hours => In 1 hour she puts up 1/5 th of the tent
Similarly a boy can put up 1/3rd of the tent in 1 hour.
=> 4 boys will put up 4/3 tents in 1 hour
=> 7 girls will put up 7/5 tents in 1 hour
In X hours, 4 boys and 3 girls together will put up the complete tent:
X*(4/3 + 7/5) = 1
=> X*(20 + 21) = 15
=> X = 15 / 41 ...Ans
Can you please post the source of your questions and only post authentic GMAT questions. CAT questions are out of scope.
~Abhay
Believe those who are seeking the truth. Doubt those who find it. -- Andre Gide
