Question

A car covers a distance in 40 minutes with an average speed of 60 km per hour.the average speed to cover the same distance in 30 minutes is

Answer 1

$\large\bf\underline{Given:-}$

A car covers a distance in 40 minutes with an average speed of 60 km per hour.

$\large\bf\underline {To \: find:-}$

Speed to cover same distance in 30 minutes.

$\huge\bf\underline{Solution:-}$

$\underbrace{ \bf \: case \: 1st : - }$

$\bf{Given}\begin{cases}\textsf{time = 40minutes }\\\textsf{speed = 60km/hr} \end{cases}$

Changing 40 minutes into hours.

$\rm \: time \: 40 \: minutes = \frac{40}{60} \: hr \\ \rm \: time \: = \frac{2}{3} \: hr$

$\large \bf \dag \: Distance = Speed × Time \\ \\ \dashrightarrow \rm \: Distance = \cancel{60} \times \frac{2}{ \cancel3} \\ \\ \dashrightarrow \rm \: \: Distance = 20 \times 2 \\ \\ \dashrightarrow \rm \: \: Distance = 40km$

$\underbrace{ \bf \: case \:2nd : - }$

speed to cover the same distance in 30 minutes:-

$\bf{Given}\begin{cases}\textsf{time = 30minutes }\\\textsf{distance = 40km} \end{cases}$

Changing 30 minutes into Hours.

$\rm \: time \: 30 \: minutes = \frac{30}{60} \: hr \\ \rm \: time \: = \frac{1}{2} \: hr$

$\large\bf \dag \: speed = \frac{distance}{time}$

$\dashrightarrow \rm \: \: speed = \frac{ \frac{40}{1} }{2} \\ \\ \dashrightarrow \rm \: \: speed = 40 \times \frac{2}{1} \\ \\ \dashrightarrow \rm \: \: speed = 80km/hr$

✦ The average speed to cover the same distance (40km) in 30 minutes is 80km/hr.

Answer 2

${\red{\huge{\bold{\underline{\underline{Answer:-}}}}}}$

• $\small\mathrm{The \: average \: speed \: to \: cover \: the \: same \: distance \: time \: taken \: by \: the \: car \: in \: 25 \: min \: is \: 96 \: km/hr.}$

$\large\mathrm\red{Given:-}$

• $\small\mathrm{A \: car \: covers \: a \: distance \: in \: 40 \: min \: with \: an \: average \: speed \: of \: 60 \: km/h.}$

$\large\mathrm\red{To \: find}$

• $\small\mathrm{What \: should \: be \: the \: average \: speed \: to \: cover \: the \: same \: distance \: time \: taken \: by \: the \: car \: in \: 25 \: min \: ?}$

$\large\mathrm\red{Solution}$

• $\small\mathrm{Let \: the \: distance \: traveled \: be \: 'x' \: km.}$

$\small\mathrm{⇢ Time \: taken = 40 minutes = 2/3 hrs}$

$\small\mathrm{⇢ Average \: speed = 60 km/hr}$

$\large\mathrm\red{The \: distance \: formula \: is }$

$\small\mathrm{⇢ Distance = Speed × Time}$

$\small\mathrm{⇢ Distance = 60 × 2/3}$

$\large\mathrm\red{Now, \: the \: time \: is \: 25 \: minute = 5/12 hr}$

$\large\mathrm\red{Then \: the \: average \: speed \: is \: given \: by,}$

$\small\mathrm{⇢ Speed = Distance/Time}$

$\small\mathrm{⇢ Speed = 40 / 5/12}$

$\small\mathrm{⇢ Speed = 96 km/hr}$

$\large\underline\mathrm\red{Therefore, the \: average \: speed \: to \: cover \: the \: same \: distance \: time \: taken \: by \: the \: car \: in \: 25 \: min \: is \: 96 \: km/hr.}$