The world record

The world record for the longest dogtail is 77/100 meters. The previous record was 1/20 meter shorter than the current record. Was the previous record holder longer than 3/4 meter?

Result

x=

Yes

No

Step-by-step explanation:

$$\begin{gathered} b=\frac{77}{100}=0.77\text{m} \\ a=b-\frac{1}{20}=\frac{77}{100}-\frac{1}{20}=\frac{77}{100}-\frac{5}{100}=\frac{77-5}{100}=\frac{72}{100}=\frac{18}{25}=0.72\text{m} \\ \Delta =a-\frac{3}{4}=\frac{18}{25}-\frac{3}{4}=\frac{72}{100}-\frac{75}{100}=\frac{72-75}{100}=\frac{-3}{100}=-\frac{3}{100}=-0.03\text{m} \\ \Delta <0 \\ x=0 \end{gathered}$$

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