Question

7. A, B and C working together on finish
work in 8 hours. A alone can do it in 10 hours
and B alone can do it in 24 hours. In how many
hours will Calone do the same work​

Answer 1

Answer:

Step-by-step explanation:

Time taken by A, B and C working together to finish a work = 8 hours 

Work done by A, B and C working together in one hour = 1/8

Time taken by A alone to finish the work = 20 hours

Work done by A in 1 hour = 1/20 

Time taken by B alone to finish the work = 24 hours

Work done by B in 1 hour = 1/24

So, work done by C  = 1/8 - (1/20 + 1/24)

Taking LCM of the denominators and then solving it.

⇒ [15 - (6 + 5)]/120

⇒ (15 - 11)/120

⇒ 4/120

⇒ 1/30 

So, C alone can do the same work in 30 hours.