Question

a train speeds past a pole in 15 seconds and a platform 100m long in 25 seconds .its length is​

Answer 1

Answer :

• Length of the train is 150m

Given :

• A train speeds past a pole in 15 seconds and a platform 100m long in 25 seconds

To find :

• Length

Solution :

• Let the length of train be x
• Let the speed be ym/sec

Given that , A train speeds past a pole in 15 seconds so ,

》x/y = 15

》y = x/15

Now Given that platform is 100m long in 25 seconds so ,

》x + 100/25 = x/15

》 15(x + 100) = 25x

》 15x + 1500 = 25x

》 1500 = 10x

》 x = 1500/10

》 x = 150m

Hence Length of the train is 150m

More Explanation :

• Speed = Distance/Time
• Distance = Speed × Time
• Time = Distance/Speed

Answer 2

Given :-

• A Train speed past a pole in 15 seconds and a platform 100m long in 25 seconds.

To find :-

• Find the Length ?

Solution :-

• Let the Length of train be x
• Let the speed by m/sec

• A train speeds in a pole in 15 seconds

$\large\dashrightarrow$$\large{\sf{\frac{x}{y}}}$= 15

$~~~~~$$\large\dashrightarrow$y = $\large{\sf{\frac{x}{15}}}$

• Platform is 100 m long in 25 second

:$\implies$x + $\large{\sf{\frac{100}{25}}}$= $\large{\sf{\frac{x}{15}}}$

$~~~~~$:$\implies$15( x + 100 ) = 25x

$~~~~~~~~~~$:$\implies$15x + 1500 = 25x

$~~~~~~~~~~~~~~~$:$\implies$1500 = 10x

$~~~~~~~~~~~~~~~~~~~~$:$\implies$x = $\large{\sf{\frac{1500}{10}}}$

$~~~~~~~~~~~~~~~~~~~~~~~~~$:$\implies$x = ${\cancel{\dfrac{1500}{10}}}$

$~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~$:$\implies$${\underline{\boxed{\pink{\frak{x = 150 ~m}}}}}$★

$\large\dag$ Hence,

• The Length of the train is = $\large{\rm\underline{150 ~m}}$