Question

P can complete a work in 45 hours .find the time taken by Q to complete the same work if they work together it in 30 hrs​

Answer 1

Let the amount of work be 1 Unit.

P takes 30 hours to complete the 1 unit of work.

In one hour amount of work done by P = (1/30) units

Let Q takes x hours to complete the 1 unit of work.

In one hour amount of work done by Q = (1/x) units

Amount of work done by P & Q together in 1 hour = (1/30)

Therefore,

(1/45) + (1/x) = (1/30)

(1/x) = (1/30) - (1/45)

(1/x) = (45 - 30)/(30*45)

(1/x) = (15)/(30*45)

(1/x) = (1)/(30*3)

1/x = 1/90

x = 90 hours ——> Answer

Answer 2

Answer:

Here is the answer....

Step-by-step explanation:

Let the amount of work be 1 Unit.

P takes 30 hours to complete the 1 unit of work.

In one hour amount of work done by P = (1/30) units

Let Q takes x hours to complete the 1 unit of work.

In one hour amount of work done by Q = (1/x) units

Amount of work done by P & Q together in 1 hour = (1/30)

Therefore,

(1/45) + (1/x) = (1/30)

(1/x) = (1/30) - (1/45)

(1/x) = (45 - 30)/(30*45)

(1/x) = (15)/(30*45)

(1/x) = (1)/(30*3)

1/x = 1/90

x = 90 hours

Hope it helps....