Question

A and B can do a piece of work in 20 days. B alone can do 1/5th of the work in 12 days. in how many days A alone can do it?​

Answer 1

Answer:

Together they can do work in = 20 days

● B can do $\tt{\frac{1}{5^{th}}}$ of the work in = 12 days

● First, we'll find in how many days, B can complete the work.

● Total work = $\tt{\frac{1}{20}}$

$\tt{\frac{1}{5^{th}}}$ of the work = $\tt{\frac{1}{5}}$ × $\tt{\frac{1}{20}}$

=> $\tt{\frac{1}{100}}$

● If B can do $\tt{\frac{1}{100}}$ work in 12 days, then it'll do $\tt{\frac{1}{20}}$ work in = 60 days

B can do the work in = 60 days

A can do the work in = $\tt{\frac{1}{20}}$ - $\tt{\frac{1}{60}}$ = $\tt{\frac{1}{30}}$ = 30 days

Thus, A will complete the work in 30 days.

Answer 2

ANSWER: THUS A CAN DO THE WORK IN 30 DAYS.

Step-by-step explanation: Together they can do work in 20 days.

B can do 1/5th of the work in 12 days.

Together's one day work=1/20.

1/5th of the work =1/5×1/20=1/100.

B can do 1/100 work in 12 days,then it"ll do work in 60 days.

B can do the work in 60 days.

Thus,A can do the work in=1/20-1/60=3-1/60=2/60=1/30=1/1/30=30 days.