



 
Hi, A little bit of algebra gets you a long way in this problem. First of all $15\% = \frac{15}{100} = 0.15$ so you have \[X  0.15X = Y\] On the left side $X$ is a common factor so the expression can be written \[X(1  0.15) = Y.\] But $1  0.15 = 0.85$ and hence \[0.85 \times X = Y.\] Filially divide both sides by $0.85$ to get \[X = \frac{Y}{0.85}.\] Thus for your example if $Y = 22,000,000$ then \[X = \frac{22,000,000}{0.85} = 25,882,352.94\] Penny  


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