5. A can do a piece of work in 8 days which B alone can do in 10 days. In how many days both working
together can do it?

In 1 day A can do 1/8 work

In 1 day A can do 1/10 work

in 1 day A+B can do (1/8 +1/10) 40rk

in 1 day A=B can do 9/40 work

so In 1/ (9/40) days A+B can do work together = 40/9 days

Step-by-step explanation:

the answer is y < -3 or   y > 3

-3y > 7 + 2

-3 y > 9

y < -3

898.1666667

step-by-step explanation:

5389/6 = 898.1666667