**Question:**

**Train $A$ and train $B$ are running on parallel tracks in the opposite directions with speeds of $36 \mathrm{~km} /$ hour and 72 $\mathrm{km} /$ hour, respectively. A person is walking in train $A$ in the direction opposite to its motion with a speed of $1.8$$\mathrm{km} /$ hour. Speed $\left(\right.$ in $\left.\mathrm{ms}^{-1}\right)$ of this person as observed from train $B$ will be close to : (take the distance between the tracks as negligible)**

$29.5 \mathrm{~ms}^{-1}$

$28.5 \mathrm{~ms}^{-1}$

$31.5 \mathrm{~ms}^{-1 \mathrm{q}}$

$30.5 \mathrm{~ms}^{-1}$

Question of from chapter.

JEE Main Previous Year 2 Sep. 2020 (I)

Correct Option: 1

**Solution:**

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