Question

Sheena, working alone can embroider a sari in 10 days while Rihana working alone can complete the same embroidery in 8 days. If both work together, how long will it take them to finish the embroidery?​

Answer 1

Answer:

In 1 day Shena can finish 1/10 work

In 1 day Rihanna can finish 1/8 work

So in 1 day both together can finish (1/10)+(1/8)=9/40 work

So 9/40 work is done in 1 day

So 1 work (full work) can be done in 40/9 days