Question

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

• A. 200 m
• B. 150 m
• C. 50 m
• D. Data inadequate

Answer 1

The correct option is B 150 m

$\text{The length of train be}x\text{meters and its speed by}y\text{meters/sec.}Then,\frac{x}{y}=15\Rightarrow y=\frac{x}{15}\frac{x+100}{25}=\frac{x}{15}\Rightarrow x=150m/s$