1/2^12 + 2/2^13 + 4/2^14 + 8/2^15 =

Question

\frac{1}{2^{12}} + \frac{2}{2^{13}} + \frac{4}{2^{14}} + \frac{8}{2^{15}} =

A. 1/2^10

B. 1/2^12

C. 15/2^15

D. 2/2^10

E. 23/2^16

gadde22 · Answer

Lcm is 2^15. So it will become like

8 + 8 + 8 + 8/2^15 = 2^5/2^15
 = 1/2^10, so option A.

Please give me Kudos if you like my explanation.

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LevanKhukhunashvili · Answer

We can reduce the fractions \frac{1}{2^12} = \frac{1}{2^12}

\frac{2}{2^13} = \frac{1}{2^12} \frac{4}{2^14} = \frac{1}{2^12} \frac{8}{2^15} = \frac{1}{2^12} So we get 4* \frac{1}{2^12} = \frac{1}{2^10} IMO Ans: A

sumi747 · Answer

After reducing each term we get 4*1/(2^12)= 1/(2^10)
IMO A

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Archit3110 · Answer

simplify expression 
we get ; 4/2^12 ; 1/2^10
IMO A

Abhishek009 · Answer

\frac{1}{2^{12}} + \frac{2}{2^{13}} + \frac{4}{2^{14}} + \frac{8}{2^{15}}

=\frac{1}{2^{12}} + \frac{1}{2^{12}} + \frac{1}{2^{12}} + \frac{1}{2^{12}}

=\frac{4}{2^{12}}

=\frac{1}{2^{10}} ; Answer must be (A)

abcxyz2019 · Answer

I would say, simply take 1/2^12 common.

--> 1/2^12   = 1/2^12  = 1/2^2 * 2^10   = 1/2^10 cheers

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1/2^12 + 2/2^13 + 4/2^14 + 8/2^15 =

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1/2^12 + 2/2^13 + 4/2^14 + 8/2^15 =

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