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Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

If s=1+(1/2)+(1/4)+(1/8)+(1/16)+(1/32) and t=1+(1/2)*s, then t exceeds s by

(A) 1/4
(B) 1/8
(C) 1/16
(D) 1/32
(E) 1/64

答案和解析

答案：E

解析：

"t exceeds s" is interpreted mathematically as the value of t-s and is evaluated as follows:

t-s = (1 + (s/2))-s

= 1 + ((1 + (1/2) + (1/4) + (1/8) + (1/16) + (1/32))/2

-(1 + (1/2) + (1/4) + (1/8) + (1/16) + (1/32))

= 1 + (1/2) + (1/4) + (1/8) + (1/16) + (1/32) + (1/64)

-1-(1/2)-(1/4)-(1/8)-(1/16)-(1/32)

= 1/64