Question

A 70 m long train runs at a speed of 75 km/hr. Calculate how long will it take to cross a platform of 105 m. ( Ans = 8 2/5 seconds)​

Answer 1

Answer:

$Time = \dfrac{42}{5} \sec$

Step-by-step explanation:

Length of train = 70 m

Length of platform = 105 m

Total length = 70 + 105

Total length = 175 m

Speed of train = 75 km/hour

                 $= 75 \times \dfrac{5}{18}$

                 $= 25 \times \dfrac{5}{6}$

$Speed \ of \ train \ = \dfrac{125}{6} \ m/sec$

Time to cross the platform =?

We know that-

$Time = \dfrac{Distance}{Speed}$

Here distance = 175 m

$Time = \dfrac{175}{\dfrac{125}{6}}$

         $= \dfrac{175 \times 6}{125}$

         $= \dfrac{7 \times 6}{5}$

$Time = \dfrac{42}{5} \sec$

Answer 2

Answer:

the given answer is best