One pump drains one-half of a pond in 3 hours, and then a second pump starts draining the pond. The two pumps working together finish emptying the pond in one and half hour. How long would it take the second pump to drain the pond if it had to do the job alone?

On average, the bottle-nosed dolphin comes up for air once every two minutes; the beluga whale, close relative, comes up for air on average once every five minutes. The number of times a bottle-dolphin would come up for air in a 24 hour period is approximately what percent greater than number of times a beluga whale would come up for air in that same period?

A certain business produced x rakes each month from November through February and shipped $\frac{x}{2}$ rakes at the beginning of each month from March through October. The business paid no storage costs for the rakes from November through February, but it paid storage costs of $0.10 per rake each month from March through October for the rakes that had not been shipped. In terms of x, what was the total storage cost, in dollars, that the business paid for the rakes for the 12 months from November through October ?

A rectangular box that is 7 inches long by 4 inches wide by 3 inches deep is carefully packed to th hold the maximum number of blocks that are 1 inch by 1 inch by 2 inches. How many blocks can be packed into the box?

A, B and C can complete a piece of work in 16, 32 and 48 days, respectively. They started working together but C left after working 4 days and B left 2 days before the completion of the work. How many days it took in total to complete the work?