Peter's calculation

Peter wrote the following: 7 1/4 - 3 3/4 = 4 2/4 = 4 1/2. Is Peter's calculation correct? Using words (math vocabulary) and numbers to explain why he is correct or incorrect.

Result

x=

Yes

No

Step-by-step explanation:

$$\begin{gathered} a=7\frac{1}{4}=7+\frac{1}{4}=\frac{7\cdot 4+1}{4}=\frac{28+1}{4}=\frac{29}{4}=7\frac{1}{4}=7.25 \\ b=3\frac{3}{4}=3+\frac{3}{4}=\frac{3\cdot 4+3}{4}=\frac{12+3}{4}=\frac{15}{4}=3\frac{3}{4}=3.75 \\ c=a-b=\frac{29}{4}-\frac{15}{4}=\frac{29-15}{4}=\frac{14}{4}=\frac{7}{2}=3\frac{1}{2}=3.5 \\ x=0 \end{gathered}$$

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