Question : A alone can do a work in 4 days, which B alone can do in 6 days. In how many days they together can do it?

Option 1: $\frac{7}{12}$

Option 2: $\frac{12}{7}$

Option 3: $\frac{12}{5}$

Option 4: $\frac{5}{12}$

Question : Avi alone can do a piece of work in 60 days while Prakash alone can do it in 80 days. In how many days will they finish it together?

Option 1: $\frac{250}{6}$ days

Option 2: $\frac{270}{6}$ days

Option 3: $\frac{240}{7}$ days

Option 4: $\frac{140}{6}$ days

Question : A alone can do a piece of work in 10 days. B alone can do the same work in 12 days. They work on alternate days starting with A. In how many days will they complete $\frac{3}{4}$th of the total work?

Option 1: $\frac{47}{3}$ days

Option 2: $\frac{50}{3}$ days

Option 3: $\frac{53}{6}$ days

Option 4: $\frac{49}{6}$ days

Question : A alone can do $\frac{1}{4}$th part of the work in 12 days. B alone can do $\frac{1}{5}$th part of the work in 4 days. In how many days can A and B together can do the same work?

Option 1: $\frac{330}{13}$ days

Option 2: $\frac{240}{17}$ days

Option 3: $\frac{210}{4}$ days

Option 4: $\frac{255}{7}$ days

Question : P alone can do a piece of work in 24 days. Q alone can do it in 30 days and R alone can do it in 20 days. In how many days they can complete it together?

Option 1: 15 days

Option 2: 18 days

Option 3: 8 days

Option 4: 10 days