Question

Answer the 7th question."DON'T SEND THE SIMILAR QUERIES.KINDLY PERFORM THE STEP BY STEP AND APPROPRIATE ANSWER".
Q.7. Amit walks from his house to school at a speed of 3 kmph and returns back at a speed of 4 kmph. If he takes 42 minutes for the whole journey, find the distance between his house and the school.

Answer 1

Dear student,
Here is the solution of your asked query:
$$\begin{gathered} \mathrm{Suppose}\mathrm{the}\mathrm{distance}\mathrm{between}\mathrm{house}\mathrm{and}\mathrm{school}\mathrm{be}\mathrm{x}\mathrm{km}. \\ \mathrm{Walking}\mathrm{speed}\mathrm{of}\mathrm{Amit}\mathrm{from}\mathrm{house}\mathrm{to}\mathrm{school}=3\mathrm{km}/\mathrm{h} \\ \mathrm{So},\mathrm{time}\mathrm{taken}\mathrm{to}\mathrm{cover}\mathrm{from}\mathrm{house}\mathrm{to}\mathrm{school}=\frac{\mathrm{x}}{3}\mathrm{h} \\ \mathrm{Also},\mathrm{walking}\mathrm{speed}\mathrm{of}\mathrm{Amit}\mathrm{from}\mathrm{school}\mathrm{to}\mathrm{house}=4\mathrm{km}/\mathrm{h} \\ \mathrm{So},\mathrm{time}\mathrm{taken}\mathrm{to}\mathrm{cover}\mathrm{from}\mathrm{school}\mathrm{to}\mathrm{house}=\frac{\mathrm{x}}{4}\mathrm{h} \\ \mathrm{Time}\mathrm{taken}\mathrm{for}\mathrm{whole}\mathrm{journey}=\frac{\mathrm{x}}{3}+\frac{\mathrm{x}}{4}=\frac{42}{60}\mathrm{h}\{\mathrm{Since},42\mathrm{minutes}=\frac{42}{60}\mathrm{h}\} \\ \Rightarrow \frac{\mathrm{x}}{3}+\frac{\mathrm{x}}{4}=\frac{42}{60} \\ \Rightarrow \frac{7\mathrm{x}}{12}=\frac{42}{60} \\ \Rightarrow \mathrm{x}=\frac{42\times 12}{60\times 7}=\frac{6}{5}\mathrm{km}=1.2\mathrm{km} \end{gathered}$$
Therefore, the distance between school and house is 1.2km.

Regards