Question

Somu had to travel certain distance. The travelled 3/5 of the distance at 40 kmph. and the remaining at 60 kmph. If the total time taken is 6 1/2hours, find the total distance he travelled ?

Answer 1

Let total distance be x,
then for 3/5 distance time taken will be
= (3x/5)/40
since time= distance/ speed
similarly,
for remaining distance,
time taken= (2x/5)/60.
now total time,
(3x/5)/40 + (2x/5)/60= 6 1/2 hrs
total distance x = 300 km

Answer 2

Answer:

The distance covered is 260 km.

Step-by-step explanation:

Given : Somu had to travel certain distance. The travelled 3/5 of the distance at 40 kmph. and the remaining at 60 kmph. If the total time taken is 6 1/2hours.

To find : The total distance he travelled ?

Solution :

Let the total distance is x km

He travelled 3/5 of the distance at 40 kmph.

i.e, distance covered is $\frac{3}{5}x$

Speed is 40 kmph.

The time taken to cover is

$T_1=\frac{D}{S}$

$T_1=\frac{\frac{3}{5}x}{40}$

$T_1=\frac{3}{200}x$

The remaining distance $x-\frac{3}{5}x=\frac{2}{5}x$

i.e, distance covered is $\frac{2}{5}x$

Speed is 60 kmph.

The time taken to cover remaining distance is

$T_2=\frac{D}{S}$

$T_2=\frac{\frac{2}{5}x}{40}$

$T_2=\frac{2}{200}x$

Total time taken is $T=6\frac{1}{2}=\frac{13}{2}hr$

According to question,

$T_1+T_2=T$

$\frac{3}{200}x+\frac{2}{200}x=\frac{13}{2}$

$\frac{5}{200}x=\frac{13}{2}$

$x=\frac{13\times 200}{2\times 5}$

$x=260km$

Therefore, The distance covered is 260 km.