A student walks from his house at 4 km/hr & reaches his school late by 5 minutes.If his speed has been 5 km/hr then he would have reached 10 minutes early.The distance of the school from his house??

Question

theviper · Answer

@mathslover @Callisto @lgbasallote Plz help:)

mathslover · Answer

sorry i am busy but may be this will help u http://www.bankexam.co.in/uploads/exam_features/1008091281348289Time%20&%20Distance.pdf

callisto · Answer

Let d be the distance and t be the time spent if he can arrive school punctually.
Formula used: speed = distance / time
''A student walks from his house at 4 km/hr & reaches his school late by 5 minutes''
5 minute = 5/60 hour = 1/12 hour

$$4 = \frac{d}{t+\frac{1}{12}}$$$$4t+\frac{1}{3} = d$$

''5 km/hr then he would have reached 10 minutes early.''
10minutes = 10/60 hour = 1/6 hour
$$5 = \frac{d}{t-\frac{1}{6}}$$$$5t - \frac{5}{6}= d$$ $$5t - \frac{5}{6}=4t+\frac{1}{3}$$$$t=\frac{7}{6}hours$$
$$d=4(\frac{7}{6})+\frac{1}{3} = 5 km$$
Is it correct? (Even though I think it is more likely to be wrong :| )

theviper · Answer

@Callisto yes u r correct:)
Thanx:)

theviper · Answer

@mathslover also