Question

Raghavendra can cover a distance in 1 hr and 24 min by covering 2/3 of the distance at 4 kmph and the remaining at 5 kmph. Find the total distance covered by him.

Answer 1

Let total distance covered by Raghavendra be x km
Distance travelled at 4 kmph speed = $\frac{2}{3}x$
Distance travelled at 5 kmph speed = $(1-\frac{2}{3})x$ = $\frac{1}{3}x$
Total time = 1 hr and 24 min = (60 + 24) min = $\frac{84}{60}$ hr = $\frac{21}{15}$ hr
Now
$Time=\frac{Distance}{Speed}$
$\frac{21}{15}=\frac{\frac{2}{3}x}{4}+\frac{\frac{1}{3}x}{5}$
$\frac{21}{15}=\frac{2}{12}x+\frac{1}{15}x$
$84=14x$
x = 6 km