Question

When Derek planted a tree it was 36 inches tall. The tree grew 1 1/4 inches per year. The tree is now 44 3/4 inches tall. How many years ago did Derek plant the tree?

Answer 1

Original Height = 36 inches.

Change in height:

$44\dfrac{3}{4} - 36 = 8\dfrac{3}{4}$

Number of years : 

$8\dfrac{3}{4} \div 1\dfrac{1}{4}$

$=\dfrac{35}{4} \div \dfrac{5}{4}$

$=\dfrac{35}{4} \times \dfrac{4}{5}$

$=7$

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Answer; Derek has planted the tree for 7 years.
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