Question

A train, travelling at a uniform speed for 360 km, would have taken 48 minutes less to travel the same distance if its speed were 5 km/hr more. Find the original speed of the train.​

Answer 1

$\huge \tt \underline \purple{Qᴜᴇsᴛɪᴏɴ♡࿐}$

A train, travelling at a uniform speed for 360 km, would have taken 48 minutes less to travel the same distance if its speed were 5 km/hr more. Find the original speed of the train.

$\huge \tt \underline \purple{Aɴsᴡᴇʀ♡࿐}$

Let the original speed of train be x km/hr

☯Time Taken = $\frac{distance}{speed}$ = $\frac{360}{x}$ Hours

☯Time taken at increase speed = $\frac{360}{x + 5}$ hours

★According to the question :-

➠ $\frac{360}{x}$

➠ $\frac{360}{x + 5}$

➠ $\frac{48}{60}$

➠ $360 \: ( \frac{1}{x} - \frac{1}{x + 5}) = \frac{4}{5}$

➠ $\frac{1800}{ {x}^ + {5x} } = \frac{4}{5}$

➠ ${x}^{2} + 5x - 2250 = 0$

➠ ${x}^{2} + (50 - 45)x - 2250 = 0$

➠ ${x}^{2} + 50x - 45x - 2250 = 0$

➠ $(x + 50)(x - 45) = 0$

➠ $x = - 50 \: or \: x = 45$

(➥ Note:- Speed can not be negative )

So,

Original speed of train = 45 km/hr...

Hope it's helpful mate :)❤️

Answer 2

see the Above attachment

hope it help,