A certain number of men can complete a work in five days less than the time taken by some women. Work completed by one man in one day is the same as the work completed by one woman in one day. Which one of the following ratio of the number of men to the number of women can satisfy the above-given condition?

(i). $2 : 5$

(ii). $10 : 3$

(iii). $9 : 7$

(iv). $10 : 7$

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.$15$ 

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. $45$ 

A and B working alone can do a work in $20$ days and $15$ days respectively. They started the work together but B left after sometime and A finished the remaining work in $6$ days. Find after how many days from start B left the work?