Question

Jayanti and seema can together do a piece of work in 10 hours. Seema alone can do it in 15 hours. How long will jayanti take to do it alone?

Answer 1

Seema alone can do a piece of work in 15 hours,

By this we can say that she will do 1/15th work every hour,
let Jayanti's 1 hour work = 1/X ,
according to the data,
(1/X + 1/15) *10 = 1

Here 1 represents the work, We multiplied 10 because it's the time taken,

so now , 10/X + 10/15 = 1,

10/X = 1-10/15

10/X = (15-10)/15

10/X = 5/15,

10/X = 1/3
X = 30,
So Jayanti can do a piece of work in 30 hours !

Hope you understand ! the answer is 30 hours !!