Question

lA , B and C can do a piece of work in 15 , 12 ,and 20 days respectively . They started the work together , but C left after 2 days . In how many days will the remaining work be completed by A and B?​

Answer 1

4 days

Step-by-step explanation:

LET,

THE WORK DONE BY A IN ONE DAY

=1/15

THE WORK DONE BY B IN ONE DAY

=1/12

THE WORK DONE BY C IN ONE DAY

=1/20

SINCE THEY STARDED AND DONE SOME WORK TOGETHER FOR 2 DAYS, THE AMOUNT OF WORK THEY COMPLETE WILL BE

= 2(1/15 +1/12+1/20)

= 2/5

SO, REMAINING WORK WILL BE=3/5

TIME TAKEN BY A AND B TO COMPLETE REMAINING WORK

(1/15+1/12)n= 3/5

(9/60) n = 3/5

n=4

THERE FORE NO. OF DAYS IN WHICH A and B

COMPLETE REMAINING WORK IS """4 DAYS""