Joe spends

Joe spends 3 3/4 hours each day of the week doing his homework, but Mirabel spends only 2 hours each day of the week on hers. How long in a week does Joe spend on his homework more than Mirabel?

Correct answer:

x =  12 ¹⁄₄ = 49/4 h

Step-by-step explanation:

$$\begin{gathered} J=3\frac{3}{4}=3+\frac{3}{4}=\frac{3\cdot 4+3}{4}=\frac{12+3}{4}=\frac{15}{4}=3.75\text{h} \\ M=2\text{h} \\ t=7\text{d} \\ {x}_1=J-M=\frac{15}{4}-2=\frac{15}{4}-\frac{2\cdot 4}{4}=\frac{15}{4}-\frac{8}{4}=\frac{15-8}{4}=\frac{7}{4}=1.75\text{h} \\ x=t\cdot x_1=7\cdot \frac{7}{4}=\frac{7\cdot 7}{4}=\frac{49}{4}=\frac{49}{4}\text{h}=12\frac{1}{4}\text{h}=12.25\text{h} \end{gathered}$$

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