16. a certain machine drills 30 holes in 8 minutes.
at that constant rate， how many holes will 4 such
machines drill in 1 hours？
（a） 300
（b） 900
（c） 960
（d） 1，200
（e） 2，560
17. tina， ed， and lauren agree to share the cost of a
gift and to make their contributions in proportion
to their ages. ed's age is of tina's age， and
lauren's age is of ed's age. if lauren's share
of the cost is $ 2.50， what is the cost of the gift？
（a） $25
（b） $20
（c） $15
（d） $12
（e） $10
18. three solid cubes of lead， each with edges 10
centimeters long， are melted together in a level，
rectangular-shaped pan. the base of the pan has inside
dimensions of 20 centimeters by 30 centimeters， and
the pan is 15 centimeters deep. if the volume of the
solid lead is approximately the same as the volume of
the molted lead， approximately how many centimeters
deep is the melted lead in the pan？
（a） 2.5
（b） 3
（c） 5
（d） 7.5
（e） 9
19. which of the following cannot be the sum of
two integers that have a product of 30？
（a） 31
（b） 17
（c） -11
（d） -13
（e） -21
20. in the rectangular coordinate system above， if
point （a， b）， shown， and the two points （4a， b） and
（2a， 2b）， not shown， were connected by straight
lines， then the area of the resulting triangular region，
in terms of a and b， would be
（a）
（b） ab
（c）
（d） 2ab
（e） 4ab
questions 21-22 refer to the following graph.
the top and bottom of each bar indicate， respectively， the highest and lowest daily number of shirts sold during
the month. the heavy line across each bar indicates the average （arithmetic mean） number of shirts sold per day
during the month.
21. what was the range in the daily number of shirts
sold during march？
（a） 20
（b） 45
（c） 50
（d） 60
（e） 70