Question

To fill a cistern, pipes A, B and C take 20 minutes, 15 minutes and 12 minutes, respectively. The time in minutes that the three pipes together will take to fill the cistern is
(a) 5
(b) 10
(c) 12
(d)15 ⅔​

Answer 1

Answer:

't' is the time taken to fill the cistern by all the three pipes then 1/t=1/t₁+1/t₂+1/t₃

t₁,t₂,t₃ are time taken by pipes A, B ,C to fill the cistern separately.

1/t=1/20+1/12+1/15

1/t=3+5+4/60

1/t=12/60

1/t=1/5

t=5min is time taken by all pipes to fill the cistern.

Answer 2

Step-by-step explanation:

t=5mins

bro

it is a correct answer