View all: JANATA BANK | ASSISTANT EXECUTIVE OFFICER (AEO) | WRITTEN MATH SOLVE | 2011
Correct Answer: 120 days
Explanation:
Let the wholejob be 1 partMasud does in 40 days = 1 part
Masud does in 1 days =$\frac{1}{40}$’ part
Masud does in18 days =$\frac{18}{40}$ part
Similarly, Karim does in 60 days = 1 part
Karim does in 18 days = $\frac{18}{60}$ part
In 18 days they together did = $\frac{18}{60}$ + $\frac{18}{40}$ = $\frac{3}{4}$
Remain = (1 -$\frac{3}{4}$ ) part =$\frac{1}{4}$ part
$\frac{1}{4}$ part is done by the three in 5 days
In 5 days they did =$\frac{1}{4}$ part
In 1 day they did =’$\frac{1}{5}$ part
Now, In 1 day Masud & Karim together does = $\frac{1}{40}$+ $\frac{1}{60}$
In 1 day Harun dees = ($\frac{1}{20}$-$\frac{1}{24}$) = $\frac{1}{120}$ part
Harun alone does $\frac{1}{120}$ part in = 1 day
Harun alone does 1 part in 120 days.