Question

A train traveling at a uniform speed passes by a platform 220 m long in 30 s and another platform 325 m long in 39 s Find.
(i) the length of train and the speed of train
I need a answer with process if you have no process don't answer otherwise your answer will be reported​

Answer 1

$\huge\bold\red{Question}$

A train traveling at a uniform speed passes by a platform 220 m long in 30 s and another platform 325 m long in 39 s Find the length of train and the speed of train.

$\huge\bold\green{Solution}$

Given , $\bold{s = t + \frac{220}{30} ...... eqn(i)}$

$\bold{s = t + \frac{325}{39} ......... eqn(ii)}$

By solving $\bold{eqn(i)}$ and $\bold{eqn(ii)}$, we get

$\bold{39 (t + 220)}$ =$\bold{ 30 (t + 325)}$

$\bold{39t + 8580 = 30t + 9750}$

$\bold{9t = 1170}$

$\bold{t = 130\:m}$

Substituting in $\bold{eqn(i)}$, we get

Speed = $\bold{130 + \frac{220}{30}}$

=$\bold{ \frac{350}{30}}$

= $\bold{11.66\: m / sec}$

On converting in $\bold{km/h}$

Speed = $\bold{\frac {18}{5}\times 11.66\:\:\:km/h}$

= $\bold{41. 976\:\:\: km/h}$

Answer 2

Given s =t + 220/30 ••••• (1)

and s= t + 325/39•••••••(2)

on solving (1) and (2), we get

39(t + 220) = 30(t + 325)

39t + 8580 = 30t + 9750

9t = 1170

t = 130 metres

Substitute in (1), we get

Speed = 130 + 220/30

= 350/30

= 11.66 m/sec =

On converting it to km/hr, we get

S= 3600 * 11.66/1000

= 41.9

= ~42