One-quarter 7426

There were 46 more apple trees than pear trees in the orchard. The storm destroyed one-quarter of apple trees and seven pear trees. There are 80 trees left. How many are left?

Correct answer:

j =  57
h =  23

Step-by-step explanation:

$$\begin{gathered} a=46+b \\ 80=a+b-(a/4+7) \\ a-b=46 \\ 3a+4b=348 \\ Pivot:Row1\leftrightarrow Row2 \\ 3a+4b=348 \\ a-b=46 \\ Row2-\frac{1}{3}\cdot Row1\to Row2 \\ 3a+4b=348 \\ -2.33b=-70 \\ b=\frac{-70}{-2.33333333}=30 \\ a=\frac{348-4b}{3}=\frac{348-4\cdot 30}{3}=76 \\ a=76 \\ b=30 \\ j=a-a/4=76-76/4=57 \end{gathered}$$

$h=b-7=30-7=23$

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