A train traveling at 80 km/h crosses another train traveling in the same direction at 26 km/h in 30 seconds. What is the combined length of both the trains?

Correct option is B

​​​Given:

Speed of the first train (v₁) = 80 km/h

Speed of the second train (v₂) = 26 km/h

Time taken to cross = 30 seconds

Formula Used:

Relative speed when two objects are moving in the same direction= $$v_{\text{relative}} = v_1 - v_2$$​​

 Distance covered (combined length of both trains)= $$\text{Distance} = \text{Speed} \times \text{Time}$$​​

Solution:

​$$v_{\text{relative}} = v_1 - v_2 = 80 \text{ km/h} - 26 \text{ km/h} = 54 \text{ km/h}\\ v_{\text{relative}} = 54 \times \frac{1000}{3600} \text{ m/s} = 15 \text{ m/s} \\ \text{Distance} = \text{Speed} \times \text{Time} = 15 \text{ m/s} \times 30 \text{ s} = 450 \text{ m} \\$$​​