Donuts 3

You pick up donuts for a party. You have 3 and 4/12 boxes of donuts. Roy picks up donuts too. He has 2 and 9/12 boxes of donuts. How many boxes of donuts do you have in all?

Correct answer:

x =  6 ¹⁄₁₂ = 73/12

Step-by-step explanation:

$$\begin{gathered} a=3\frac{4}{12}=3+\frac{4}{12}=\frac{3\cdot 12+4}{12}=\frac{36+4}{12}=\frac{40}{12}=\frac{10}{3}=3\frac{1}{3}\doteq 3.3333 \\ b=2\frac{9}{12}=2+\frac{9}{12}=\frac{2\cdot 12+9}{12}=\frac{24+9}{12}=\frac{33}{12}=\frac{11}{4}=2\frac{3}{4}=2.75 \\ x=a+b=\frac{10}{3}+\frac{11}{4}=\frac{40}{12}+\frac{33}{12}=\frac{40+33}{12}=\frac{73}{12}=6\frac{1}{12}=6.0833 \end{gathered}$$

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