Question

Ghanina can correct a stack of papers in 5 hours and taruf can correct them in 4 hours how long does it take them to correct the papers together

Answer 1

t = time required to do the job
1 = stack of completed papers

t/5 + t/4 = 1

Multiply by 20 (4x5)

5t+4t =20
9t =20
t = 20/9
t = 2.22 hrs
t = 2 + 0.22(60)
t = 2hrs 13min

I hope that’s helps you :)