SAT考試數(shù)學練習題 6

字號:

1. The distance from town A to town B is five miles. C is six miles from B. Which of the following could be the distance from A to C?
    I 11
    II 1
    III 7
    A. I only
    B. II only
    C. I and II only
    D. II and III only
    E. I, II, or III.
    Correct Answer: E
    解析:
    Do not assume that AB and C are on a straight line. Make a diagram with A and B marked 5 miles apart. Draw a circle centered on B, with radius 6. C could be anywhere on this circle. The minimum distance will be 1, and maximum 11, but anywhere in between is possible.
    2. √5 percent of 5√5 =
    A. 0.05
    B. 0.25
    C. 0.5
    D. 2.5
    E. 25
    Correct Answer: B
    解析:
    We can write the statement mathematically, using x to mean ‘of’ and /100 for ‘per cent’. So ( √5/100) x 5√5 = 5 x 5 /100 = 0.25
    3. If pqr = 1 , rst = 0 , and spr = 0, which of the following must be zero?
    A. P
    B. Q
    C. R
    D. S
    E. T
    Correct Answer: D
    解析:
    If pqr = 1, none of these variable can be zero. Since spr = 0 , and since p and r are not zero, s must be zero. (Note that although rst = 0, and so either s or t must be zero, this is not sufficient to state which must be zero)
    4.
    A. 1/5
    B. 6/5
    C. 6³
    D. 64 / 5
    E. 64
    Correct Answer: E
    解析:
    65 = 64x 6
    (64 x 6) - 64 = 64(6 - 1) = 64 x 5 Now, dividing by 5 will give us 64
    5. -20 , -16 , -12 , -8 ....
    In the sequence above, each term after the first is 4 greater than the preceding term. Which of the following could not be a term in the sequence?
    A. 0
    B. 200
    C. 440
    D. 668
    E. 762
    Correct Answer: E
    解析:
    All terms in the sequence will be multiples of 4. 762 is not a multiple of 4