GRE-Math-Questions-to-Know-by-Test-Day-2nd-Edition_pag200

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Answers ‹ 191
198. 113 The area equals π ≈ =r (3.14)(6 in) 113.04 in2 2 2 .
199. 50 By counting the grid marks on the figure, you can determine that the box will 
have length 5 cm, width 5 cm, and height 2 cm. The volume, V, is length times width times 
height. Thus, = =V (5 cm)(5 cm)(2 cm) 50 cm3.
200. 180 The length, l, of the shawl in inches is 6(9 inches) = 54 inches. Its width, 
w, is 4(9 inches) = 36 inches. Its perimeter, P, is +l w2 2 . Thus,
P = 2(54 inches) + 2(36 inches) = 180 inches
201. 30 Given that the medians in a triangle intersect at a point that is two-thirds the 
distance from each vertex to the midpoint of the opposite side, then, FB = DB2
3
 and DF = 
15 = DB1
3
. Hence, FB = DB2
3
 = = =DB2
1
3
2(15) 30.
202. 
1166
99
 The ratio of the area of ABCDE to the area of HIJKL is the square of the ratio of 
corresponding sides; 4
3
2
 = 16
9
.
203. 67 In one revolution, the wheel will travel a distance equal to its circumference, 
π ≈d (3.14)(25 inches). Converting 5 miles
hour
 into revolutions per minute (rpm) = 
5
miles
hour
5,280 feet
1 mile
12 inches
1 foot
1 hour
60 minutes
1 revolution
(3.14)(25 inches )
67⋅ ⋅ ⋅ ⋅ ≈ rpm.
204. 62 Triangle ABC is an equilateral triangle. Using the formula for the area of an 
equilateral triangle, the area =
 = = ≈A s 3
4
12 3
4
62
2 2
 
 Tip: If you do not recall that the area of an equilateral triangle is s 3
4
2
, you can construct 
an altitude of the triangle. The altitude divides the equilateral triangle into two ° ° °30 -60 -90 
right triangles. You can use one of these right triangles to determine that the length of the 
altitude is s 3
2
, and thus:
 A bh sh s s s1
2
1
2
1
2
3
2
3
4
2
= = = = 
205. 8 Let n = the number of sides of the polygon. The sum of the measures of the exterior 
angles of any convex polygon is °360 . Thus, ° = °
n
360 45 ; 45n = 360; n = 8.
06_McCune_Answer.indd 191 2/21/22 4:47 PM