Sarvesh, Nitin and Sundhar can do a piece of work in $12$ days, $15$ days and $20$ days respectively. They started the work together and after $2$ days Nitin left the work and Sundhar left the work before $2$ days of finishing. How much time did it take to complete the work? 

Ten people can do a work in $30$ days. In how many days, can 15 people complete double the work - 

1.$40$

2. $25$

3. $20$

4. $45$ 

X can do 5 times faster work than that of Y and so it takes 36 days less than Y. Find the time in which X alone can complete the work?

G is twice as fast as S in doing work. If G can do a work in $30$ days less than S, how many days will they take to complete the work together? 

1.$25$
2. $20$
3. $22$
4.$15$