Find the percentage change from question given below

      

If $2^{x + 5} = (\frac{1}{16})^{-1}$ and 4^{2x - y} =$\frac{1}{4}$ increase 105 in the ratio $y - x:\frac{1}{3}y$ and find the percentage change.

  

Answers

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x + y = 4 x 2

4x - 2y = -2 x 1

2x + 2y = 8

$\frac{4x - 2y = -2}{6x = 6}$

x = 1

y = 3

$y - x : \frac{1}{3}y$ = 2:1

105 x 2 = 210

Percentage change = $\frac{105}{105} \times 100$ = 100%

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raphael answered the question on January 16, 2017 at 10:12

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