Question

1. the maximum posted speed limit on the u.s. interstate highway system may be found in rural areas of several western states. this maximum speed is 75 miles per hour or 121 kilometers per hour. what is the distance in kilometers, traveled by a car moving continuously at this speed for 3 hours and 20 minutes?

Explanation:

Step1: Convert time to hours

First, convert 20 minutes to hours. Since 1 hour = 60 minutes, 20 minutes = $\frac{20}{60}=\frac{1}{3}$ hours. Then the total time $t = 3+\frac{1}{3}=\frac{9 + 1}{3}=\frac{10}{3}$ hours.

Step2: Use the formula \(d=v\times t\)

The speed \(v = 121\) km/h. Using the formula for distance \(d=v\times t\), substitute \(v = 121\) and \(t=\frac{10}{3}\). So \(d=121\times\frac{10}{3}=\frac{1210}{3}\approx403.33\) km.

Answer:

\(\frac{1210}{3}\approx403.33\) km