If the operation @ is defined for all integers a and b by a@b = a + b – ab, which of the following statements must be true for all integers a, b and c? I. a@b = b@a II. a@0 = a III. (a@b)@c = a@(b@c) (A) I only (B) II only (C) I […]
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Circular gears P and Q start rotating at the same time at constant speeds. Gear P makes 10 revolutions per minute and Gear Q makes 40 revolutions per minute. How many seconds after the gears start rotating will gear Q have made exactly 6 more revolutions than gear P? (A) 6 (B) 8 (C) 10
Three grades of milk are 1 percent, 2 percent and 3 percent fat by volume. If x gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to give x+y+z gallons of a 1.5 percent grade, what is x in terms of
If n denotes a number to the left of 0 on the number line such that the square of n is less than 1/100, then the reciprocal of n must be (A) Less than -10 (B) Between -1 and -1/10 (C) Between -1/10 and 0 (D) Between 0 and 1/10 (E) Greater than 10 Correct
In the rectangular coordinate system above, the area of triangular region PQR is (A) 12.5 (B) 14 (C) 10√2 (D) 16 (E) 25 For GMAT geometry questions be active with diagrams. Don’t be satisfied with what you’re given. Try to make simple additions that provide more information (inferences). In general when trying to find
