To make some repairs to a school building, Garrett's Construction Company mixes $12\frac{2}{3}$ tons of plaster. They only use $9\frac{1}{3}$ tons of it though. How much plaster do they have left? $\newline$ Write your answer as a fraction or as a whole or mixed number. $\newline$ $\_\_\_$ tons

Full solution

Q. To make some repairs to a school building, Garrett's Construction Company mixes

12\frac{2}{3}

tons of plaster. They only use

9\frac{1}{3}

tons of it though. How much plaster do they have left?

\newline

Write your answer as a fraction or as a whole or mixed number.

\newline

\_\_\_

tons

Convert to improper fractions: Step $1$ : Convert mixed numbers to improper fractions for easier calculation. $\newline$ $12\frac{2}{3} = (12 \times 3 + 2)/3 = \frac{38}{3}$ tons $\newline$ $9\frac{1}{3} = (9 \times 3 + 1)/3 = \frac{28}{3}$ tons
Subtract to find remaining plaster: Step $2$ : Subtract the amount of plaster used from the total amount mixed to find the remaining plaster. $\frac{38}{3}$ tons - $\frac{28}{3}$ tons = $\frac{10}{3}$ tons