Question

One pipe can fill a cistern in (x-2) hrs and the other pipe can fill the same cistern in (x+7) hrs.if both the pipes when opened together take 6 hrs to fill the empty cistern.find the value of x.

Answer 1

It takes half hour, with together pipe

Answer 2

Answer:

8 hours

Step-by-step explanation:

Time taken by 1st pipe = x+2

Time taken by 2nd pipe= x+7

Portion of

Cistern filled by pipe 1 =1/x+2

cistern filled by pie 2 in 1 hour= 1/x+7

cistern filled in 6 hours by both the pipes together=

[1/ x+2 + 1/x+7]6=1

1/ x+2 + 1/x+7=1/6

solve this, its a quadratic formulae