Sonya

Sonya, Jill, and Donna run each Monday. Jill ran 6/12 of an hour, and Donna ran 5/12 of an hour. If the girls ran a total of one whole hour, what fraction of an hour did Sonya run?

Correct answer:

S =  1/12 h

Step-by-step explanation:

$$\begin{gathered} J=\frac{6}{12}=\frac{1}{2}=0.5\text{h} \\ D=\frac{5}{12}\doteq 0.4167\text{h} \\ S+D+J=1=\frac{1}{1}\text{h} \\ S=\frac{1}{1}-D-J=\frac{1}{1}-\frac{5}{12}-\frac{1}{2}=\frac{12}{12}-\frac{5}{12}-\frac{6}{12}=\frac{12-5-6}{12}=\frac{1}{12}=\frac{1}{12}\text{h}=0.0833\text{h} \end{gathered}$$

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