Question

Some school children went on an excursion by a bus to a picnic spot at a distance of 300 km. While returning, it was raining and the bus had to reduce its speed by 5km/hr and it took two hours longer for returning. Find the time taken to return

Answer 1

Here u go
Hope it helps ya.......

Answer 2

Hey

Let the speed be x kmph
Distance while going = 300 km
So , time taken = 300 / x

While returning ,
distance = 300 km
speed = ( x - 5 ) kmph
So , time taken = 300 / x - 5

A/q , second time is two hours longer than that of first .

So ,
300 / x - 5 = 300 / x + 2
$= > 300 \div x - 5 - 300 \div x = 2$
$= > 300(1 \div x - 5 - 1 \div x) = 2$

$= > x - (x - 5) \div x(x - 5) = 2 \div 300$
$= > 5 \div {x}^{2} - 5x = 1 \div 150$
$= > {x}^{2} - 5x = 1 \div 750$

$= > {x}^{2} - 5x - 750 = 0$

$= > {x}^{2} - 30x + 25x - 750 = 0$

$= > x(x - 30) + 25(x - 30) = 0$

$= > (x - 30)(x - 25) = 0$

So ,

x = 30

Hence , the speed is 30kmph .
But speed fo second case = 25 kmph .
So ,
time = 300 / 25
= 12 hours .


thanks :)

Keep loving , keep smiling !!