A student must leave for campus in 10 minutes. Unfortunately, he is snowed in. He can shovel the driveway in 18 minutes, and his brother claims to be able to do it in 14 minutes. If they shovel together, how long will it take?
To find out how long it will take for the student and his brother to shovel the driveway together, we can use the formula:
1/(time taken by student) + 1/(time taken by brother) = 1/(time taken together)
1/18 + 1/14 = 1/x
Multiplying both sides by 252 (the least common multiple of 18 and 14), we get:
14 + 18 = 252/x
32 = 252/x
x = 252/32
x = 7.875
Therefore, it will take approximately 7.875 minutes for the student and his brother to shovel the driveway together. This is equivalent to 7 minutes and 52.5 seconds.