question by each answer choice, starting with the highest answer choice because the question
asks for the greatest. 24 and 48 are factors of 96 and 144, but not of 108, so (H) and (K) must
be eliminated. 18 and 36 are factors of 108 and 144, but not of 96, so (G) and (J) must be
eliminated. That leaves (F) as the correct answer because 12 divides evenly into all three
numbers.
17 . B You’ll need to know the formula for volume of a cylinder: V = πr^2 h. So plug the known height
(10") into the formula, and set it equal to the known volume: 40π = πr^2 (10). 6π = πr 2 (4).
Solve from here, and you will find that r = 2. You can also PITA because the answer choices
represent the radius in that formula.
18 . H This problem is very difficult to visualize, so make sure you draw a figure. Since W
represents 3:00, count the hours in the directions indicated in the problem, and mark the
points that you reach. X will be 7:00; Y will be 6:00, and Z will be 10:00. So the order,
clockwise, will be W, Y, X, Z.
19 . D The trouble with this problem is that it looks more complicated than it is. Since a represents
the number of days and the problem asks you about Day Four, plug 4 in for a, and solve the
equation. 3^4 is 81 and 81(12) is 972 tribbles.
20 . G The best approach is to Plug In. You need the formula for area of a triangle: bh. The two
triangles have the same base, so start there—plug in 5, for instance. Then Plug In for the
heights; try 4 for the larger and 2 for the smaller. Now you can compute the respective areas.
For the larger, (5)(4) = 10 square feet (the problem calls this y), and for the smaller, (5)
(2) = 5 square feet. So the final step is to re-read the problem and confirm what you’re being
asked for. Y = 10, and xY = 5 , so x = .
21 . A To simplify the expression, distribute the negative to every term in the second set of variables
and drop the parentheses: 2x + 3y + 4z − 6x + 7y − 8z. Combine like terms to get −4x + 10y −
4 z. Choices (B), (C), (D), and (E) forget to distribute the negative to at least one of the terms.
22 . J Use SOHCAHTOA for right triangles: CAH means cosθ = , which is .
Remember to identify the adjacent and opposite legs of the triangle relative to angle θ.
Choice (G) incorrectly gives the adjacent leg as x rather than y; (F) gives tan θ; (H) gives cot
θ; and (K) gives sec θ.
