Answer:
The speed of slower car is 55 miles per hour.
Step-by-step explanation:
Given as :
The speed of slower car = [tex]s_2[/tex] = s mph
The speed of faster car = [tex]s_1[/tex] = ( s + 20 ) mph
The distance cover by slower car = [tex]d_2[/tex] = 165 miles
The distance cover by faster car = [tex]d_1[/tex] = 225 miles
The time taken by both cars for travelling = t hours
The speed of the cars remains constant
Now, According to question
∵ Time = [tex]\dfrac{\textrm Distance}{\textrm Speed}[/tex]
So, For slower car
t = [tex]\dfrac{d_2}{s_2}[/tex]
Or, t = [tex]\dfrac{165}{s}[/tex] ............1
So, For faster car
t = [tex]\dfrac{d_1}{s_1}[/tex]
Or, t = [tex]\dfrac{225}{s+20}[/tex] ............2
Now, equating both the equations
I.e [tex]\dfrac{225}{s+20}[/tex] = [tex]\dfrac{165}{s}[/tex]
By cross multiplying
Or, 225 × s = 165 × (s + 20)
Or, 225 s = 165 s + 3300
Or, 225 s - 165 s = 3300
Or, 60 s = 3300
∴ s = [tex]\dfrac{3300}{60}[/tex]
I.e s = 55 miles per hour
So , The speed of slower car = [tex]s_2[/tex] = s = 55 miles per hour
Hence , The speed of slower car is 55 miles per hour. Answer
