Question : Working 12 hours per day, Raj can complete a work in 12 days. How many hours per day he should work to finish the same work in 9 days?

Option 1: 20 hours

Option 2: 24 hours

Option 3: 12 hours

Option 4: 16 hours

Question : S alone can do a piece of work in 14 days. T alone can do the same work in 21 days. U alone can do the same work in 28 days. Working together, in how many days will they complete the work?

Option 1: $\frac{84}{13}$ days

Option 2: $\frac{77}{13}$ days

Option 3: $\frac{71}{13}$ days

Option 4: $\frac{87}{13}$ days

Question : 12 men can complete a work in 6 days working 4 hours per day. If 4 men work 8 hours per day, then in how many days the same work will be completed?

Option 1: 8 days

Option 2: 6 days

Option 3: 9 days

Option 4: 10 days

Question : X and Y together can do a work in 10 days. Y and Z together can do the same work in 15 days. Z and X together can do the same work in 12 days. In how many days can Z alone do the same work?

Option 1: 80 days

Option 2: 60 days

Option 3: 40 days

Option 4: 50 days

Question : A alone can do $\frac{1}{10}$th part of a work in 8 hours. B alone can do $\frac{1}{5}$th part of the same work in 4 hours. If they work together, then how many hours will they take to complete $\frac{9}{16}$th part of the same work?

Option 1: 9 hours

Option 2: 5 hours

Option 3: 8 hours

Option 4: 4 hours