Question

Sonia is thrice faster than her sister Anu and can alone complete a piece of work in 15 days.
Find the number of days to complete the work, if Sonia and Anu works together.​

Answer 1

Answer:

11.25 days

Step-by-step explanation:

Lets call the piece of work-W

Sonia-S

Anu-A

S will complete W in 15 days or 1/15 W/day.

A will complete W in 45(15x3) days or 1/45 W/day

A+S will complete 1/15 + 1/45 W/day or 4/45 W/day

Lets call the number of days required for both of them to Complete the work together as X days

i.e 4/45 W/day x X days= W

rearranging X days= W *45/(4 W)

X days= 11.25 days

Hence Sonia and Anu will complete the work together in 11.25 days