Train Speed: 150m in 25 sec - Find Length

[alijan kk]

Homework Statement

A train speeds past a pole in 15 seconds and a plate form 100 m long in 25 seconds. Its length is :

Homework Equations

The Attempt at a Solution

x/15 = (x+100)/25

after solving this equation
x= 150.

but the ans is 180 m ? what should be the correct ans.

 

[PeroK]

Homework Statement

A train speeds past a pole in 15 seconds and a plate form 100 m long in 25 seconds. Its length is :

Homework Equations

The Attempt at a Solution

x/15 = (x+100)/25

after solving this equation
x= 150.

but the ans is 180 m ? what should be the correct ans.

$150m$ looks correct to me.

 

[mfb]

I get 150 m as well, and I don't see an obvious mistake that would lead to 180 meters.

 

[alijan kk]

$150m$ looks correct to me.

A playstore app gives that answer,,, must not be a good app

THANKS FOR YOUR HELP