Question

You plant a tree that is 36 inches tall. After one year, the tree is 43 inches tall. Write an expression which describes the percent of increase in the trees height?

Answer 1

36 - 100%
43 - x  %

we multiply by cross ->  36 * x = 100 / 43 

we should remove '100%' from new value, because we find only increase.. no new value in percent.

x + 100 = (43 * 100)/36 

x =  4300/36 - 100
x = 119+ 16/36 -100
x = 19 +4/9

Answer 2

$\frac{(h_{f}-h_{o})}{h_{o}} *100$

$\frac{(43-36)}{36} *100$

$\frac{7}{36} *100$

$0.1944*100$

19.44

19.44% increase