262 MCGRAW-HILL’S SAT
- If (m + 1)(n+ 1) = 1, which of the following can
be true?
I. mand nare both positive.
II. mand nare both negative.
III. mis positive and nis negative.
(A) II only
(B) III only
(C) I and II only
(D) I and III only
(E) II and III only - If pis a prime number greater than 5 and q is
an odd number greater than 5, which of the fol-
lowing must be true?
I. p+ qis nota prime number.
II. pqhas at least three positive integer
factors greater than 1.
III. is notan integer.
(A) I only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and IIIq
pSAT Practice 7:Thinking Logically
Use logical methods to solve each of the following
SAT questions.
- If a> band b(b – a) > 0, which of the following
must be true?
I. b< 0
II. a < 0
III. ab< 0
(A) I only
(B) II only
(C) I and II only
(D) I and III only
(E) I, II, and III
A, B, C, and Dare the consecutive vertices of a
quadrilateral.
∠ABCand ∠BCDare right angles.- If the two statements above are true, then which
of the following also must be true?
(A) ABCDis a rectangle.
(B) is parallel to.
(C) is parallel to.
(D) Triangle ACDis a right triangle.
(E) Triangle ABDis a right triangle.- The statement a⇔bis defined to be true if and
only if. Which of the following is true?
(A) 3 ⇔ 5
(B) 5 ⇔ 3
(C) 4 ⇔ 2
(D) 6 ⇔ 4
(E) 7 ⇔ 5ab
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