A cyclist rides from DeKalb to Rock-
ford, a distance of 40 miles. His return trip takes
2 hours longer, because his speed decreases by
10 mph. How fast does he ride each way?

Respuesta :

The Speed of onward and return journey will be "20 mph and 10 mph".

Let,

  • The speed = S mph.

According to the question,

Time taken,

  • t₁ = [tex]\frac{40}{S+10}[/tex]

Return Journey travel time,

  • t₂ = [tex]\frac{40}{S}[/tex]

then,

→ [tex]\frac{40}{S} -\frac{40}{S+10} =2[/tex]

S = 10, -20 (negative)

→ [tex]t_1 = \frac{40}{20}[/tex]

      [tex]= 2 \ hr[/tex]

→ [tex]t_2 = \frac{40}{10}[/tex]

      [tex]= 4 \ hr[/tex]

hence,

→ The speed for onward journey will be:

= [tex]\frac{40}{2}[/tex]

= [tex]20 \ mph[/tex]

→ The speed for return journey will be:

= [tex]\frac{40}{4}[/tex]  

= [tex]10 \ mph[/tex]

Learn more:

https://brainly.com/question/2126967