Question

If a train crosses a 96 meter long platform in 12 seconds and a 141 meter long platform in 15 seconds, what will be the length of the train​

Answer 1

Answer:

(96+x)/12=(14l+X)/15

5(96+x) = 4 (141+x)

480+5x=564+4x

x = 84

Length of the train 84m.

Answer 2

If a train crosses a 96 meter long platform in 12 seconds then the length of train is 84 cm

Solution:

Let the length of the train be ‘l’ metre and the speed be constant throughout the journey.

According to the question,

$\frac{96+l}{12}=\frac{141+l}{15}$  

$\Rightarrow \frac{96+l}{4}=\frac{141+l}{5}$ [Cancelling 12 and 15 by 3]

⇒5×(96+l) = 4×(141 + l)

⇒ 480 + 5l = 564 +4l

⇒ 5l - 4l = 564 -480

⇒ l = 84

Thus the length of the train is 84 metre.