Question

1. Worker A takes 15 hours to do a job. Worker B takes
10 hours to do the same job. How long should it take
both A and B, working together but independently,
to do the same job?
a) 12.5 hours b) 10 hours
d) 4 hours
​

Answer 1

I think so it will take 10 hours because we will do subtract

Answer 2

Answer:

actual answer is 6 . though options the nearest one is 4

Step-by-step explanation:

1/15 + 1/10 = 5/30

1× 30/5 = 6