Question

What is the value of Y?

Answer 1

Answer:

40 kmph or 40 km/h

Step-by-step explanation:

let the distance from souce to destination be y

and the avarage speed for 2nd jounet be x (not a 2 variable equation)

time taken in 1st journey = distance/time =y/60

time taken in 2nd journey = distance/time = y/x

time taken for whole journey = total distance/ speed (speed here is avarage) = 2y/48

also total time = time taken in 1st journey+ time taken in 2nd journey

2y/48 = y/60 + y/x

2/48 = 1/60 + 1/x

1/24 = 1/60 + 1/x

1/24 - 1/60 = 1/x

(5-2)/120 = 1/x

3/120 = 1/x

1/40 = 1/x

40 = x

x = 40

x = 40 km$h^{-1}$ or ≈ 11.12 m$s^{-1}$

Answer 2

Answer:

40 kmph or 40 km/h

Step-by-step explanation:

Let the distance from source to destination be 'y'

and the average speed for 2nd joined be 'x' (now no longer 2 variable equation)

Time taken in 'first journey' =  '$\frac{distance}{time}$ ' = $\frac{y}{60}$

Time taken in 'second  journey' =  ' $\frac{distance}{time}$'  =  $\frac{y}{x}$

Time taken for entire journey =  total   $\frac{distance}{time}$ (speed here is average) =  $\frac{2y}{48}$

Also total time = Time taken in first journey + Time taken in second journey

$\frac{2y}{48}$ = $\frac{y}{60}$ +  $\frac{y}{x}$

$\frac{2y}{48}$ = $\frac{1}{60}$ +  $\frac{1}{x}$

$\frac{1}{24}$ =  $\frac{1}{60}$ + $\frac{1}{x}$

$\frac{1}{24}$ - $\frac{1}{60}$ =  $\frac{1}{x}$

$\frac{5-2}{120}$ = $\frac{1}{x}$

$\frac{3}{120}$ = $\frac{1}{x}$

$\frac{1}{40}$ =  $\frac{1}{x}$

40 = x

x = 40

x = 40 $\frac{km}{h}$ or ≈ 11.12 $\frac{m}{s}$.