GRE-Math-Questions-to-Know-by-Test-Day-2nd-Edition_pag227

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333. (D) Let d = the distance in miles from camp. Make a sketch, filling in the question 
information.
3 m
iles
3 miles
3 miles
4 
m
ile
s
d
7 
m
ile
s
 From the sketch, d is the length of the hypotenuse of a right triangle with legs of 
lengths 3 miles and 4 miles. Therefore, d is 5 miles. Tip: Knowing Pythagorean triples (such 
as 3, 4, 5) can be very helpful when working with right triangles.
334. (E) First, find the volume of one 4-inch cube. Then, find the volume of the crate 
by multiplying the volume of one 4-inch cube by 81. The volume of one 4-inch cube is 
=(4 in) 64 in3 3. The volume of the crate is (81)(64 in )3 = 5,184 in3.
335. (D) Make a sketch, filling in the question information.
30°
60°
2x2x
xx
12 in
 The angles in an equilateral triangle each measure 60°. Also, in an equilateral triangle, 
an altitude bisects the angle at the vertex from which it is drawn and the side to which it is 
drawn. The altitude shown is the leg opposite the 60° angle in a 30°-60°-90° right triangle. 
The sides of a 30°-60°-90° right triangle are in the ratio 1: 3 : 2. Omitting units for con-
venience, set up a proportion and solve for x and 2x.
=x
12
1
3
; so = = =x 12
3
12 3
3
4 3 and =x2 8 3.
 Hence, the area = =1
2
(8 3)(12) 48 3.
07_McCune_Answer.indd 218 2/21/22 4:37 PM