P is 20 more efficient than Q how much time will they working together take to complete a job which ......

P is 20 % more efficient than Q, how much time will they working together take to complete a job which P alone could have done in 20 days ?

Answer & Explanation
Answer – B.11 days
Explanation :
P : Q = 100 : 120
10/12 = 20/x
12/10 = x/20
X = 24
Q = 1/24 or 20*120/100 = 24
P+Q = 1/20 + 1/24
= 24+20/480 = 44/480 = 10.91 = 11 days

By: Manpreet kaur