Question

A, B, and C together can complete a job in 14 days. If A and B together can complete the same job in 21 days, how many days will it take for C to
complete the job?
28
427
42
Cannot be found
I Do Not Know

Answer 1

Answer:

A, B, and C together can complete a job in 14 days. If A and B together can complete the same job in 21 days,so , 28 days will it take for C to

complete the job.

Answer 2

Answer:

          people                 : a+b+c     a+b       c

days to complete work :   14           21        x

14×(a+b+c) = 21(a+b)

a+b+c = 21(a+b)/14 = 3(a+b)/2

2(a+b+c) = 3(a+b)

2a+2b+2c = 3a+3b

2c = a+b

a+b = 2c   [1]

21(a+b) = cx

21(2c) = cx  (by  [1] )

42c = cx

x = 42