Question

a truck drove at an average rate of 45 miles per hour on the highway and 20 miles per hour one it entered the city. If it made the 100 mile trip in 3 hrs , how much of the trip is in the city

Answer 1

Answer: Suppose x represents the distance traveled in the city, and y represents the distance traveled on the highway. We can create a system of equations based on the given information:

x + y = 100 (total distance traveled is 100 miles)

x/20 + y/45 = 3 (total time taken is 3 hours)

To solve for x, we can use the first equation to express y in terms of x:

y = 100 - x

Then we can substitute this expression for y in the second equation:

x/20 + (100 - x)/45 = 3

Next, we can simplify the equation by multiplying both sides by the least common multiple of the two denominators (900):

45x + 20(100 - x) = 3 * 900

Simplifying this equation gives:

45x + 2000 - 20x = 2700

25x = 700

x = 28

Therefore, the truck traveled 28 miles in the city, and 100 - 28 = 72 miles on the highway.

Explanation: