Miss Susan

Miss Susan cuts a board that is 16 feet long into 3 equal pieces. Then realizes that the pieces she cut each need to be 1 and 1/4 feet longer. How long does each piece of board need to be?

Correct answer:

x =  6 ⁷⁄₁₂ = 79/12 ft

Step-by-step explanation:

$$\begin{gathered} a=16/3=\frac{16}{3}\doteq 5.3333\text{ft} \\ b=1\frac{1}{4}=1+\frac{1}{4}=\frac{1\cdot 4+1}{4}=\frac{4+1}{4}=\frac{5}{4}=1.25\text{ft} \\ x=a+b=\frac{16}{3}+\frac{5}{4}=\frac{64}{12}+\frac{15}{12}=\frac{64+15}{12}=\frac{79}{12}=\frac{79}{12}\text{ft}=6\frac{7}{12}\text{ft}=6.5833\text{ft} \end{gathered}$$

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