下面是几道
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)