To find Johan's rate of speed (r) in miles per hour, we can use the distance formula \( d = rt \), where:
- \( d \) = distance traveled
- \( r \) = rate of speed
- \( t \) = length of time traveled
We know from the problem that:
- \( d = 35 \) miles
- \( t = 1.75 \) hours
We need to solve for \( r \). Rearranging the formula gives us:
\[ r = \frac{d}{t} \]
Now, substituting in the known values:
\[ r = \frac{35 \text{ miles}}{1.75 \text{ hours}} \]
Calculating that:
\[ r = 20 \text{ miles per hour} \]
Therefore, Johan travels at a rate of 20 miles per hour.
This conclusion can be interpreted in the real-world context as follows: If Johan rides his bicycle for 1.75 hours and covers a total distance of 35 miles, it indicates he maintains an average speed of 20 miles per hour throughout his ride.