Summer Vacations Kick Off This Weekend - The Solutions
05/24/2004

The total trip will be 600 miles. If we divide this by 22, we see that the roundtrip will require 27.273 gallons of gasoline. If each gallon costs $2.11, the gas for the roundtrip will cost 27.27 ´ 2.11 = $57.55. (If the number of gallons of gas needed is rounded to 27.27, the total cost only comes out to $57.54.)

If the bill had been split nine ways, then each person would be responsible for $14.95. However, it was decided that a child’s meal should not be weighted the same as an adult’s meal. Since there were six adults and three children, and it was decided that a child’s portion of the bill should be equal to a third of an adult’s portion of the bill, we can really count the three kids as one adult and assume that there were seven adults. Dividing the entire bill by seven, we see that an adult’s portion of the bill is $19.26. This means that a kid’s portion is 19.26 ¸ 3 = 6.42. Therefore, the Zappones paid 2(19.26) + 1(6.42) = $44.94.

Since we’re told that at least three of the rolls were 40-pointers, we know those accounted for 120 of the 180 points. This means that her remaining six rolls resulted in 60 points. (Note that if the combinations listed below only include three rolls, it’s understood that the remaining three rolls resulted in zero points.) A total of 60 points could be accomplished in the following ways: (one 50, one 10), (one 40, one 20), (one 40, two 10), (two 30), (one 30, one 20, one 10), (one 30, three 10), (three 20), (two 20, two 10), (one 20, four 10) and (six 10). This is a total of 10 combinations.