AbeNeedsAnswers wrote:The value of [2^(−14) + 2^(−15) + 2^(−16) + 2^(−17)]/ 5 is how many times the value of 2^(−17)?
A. 3/2
B. 5/2
C. 3
D. 4
E. 5
C
Say the value of [2^(−14) + 2^(−15) + 2^(−16) + 2^(−17)]/ 5 is x times the value of 2^(−17).
We then need to get the value of x.
=> [2^(−14) + 2^(−15) + 2^(−16) + 2^(−17)] / 5 = 2^(−17)*x
Taking 2^(−17) common from the RHS. We get,
2^(−17)[[2^(3) + 2^(2) + 2^(1) + 1] / 5] = 2^(−17)*x
=> [2^(3) + 2^(2) + 2^(1) + 1] / 5 = x; 2^(−17) gets cancelled
= [8 + 4 + 2 + 1] /5 = x
= [15] /5 = x
[spoiler]x = 3[/spoiler].
The correct answer:
C
Hope this helps!
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