Distance, Rate, and Time

Katie is determining the time it will take to travel 405 miles by train. The train travels 90 miles per hour.
Question 1
Consider the formula d = rt, where d represents distance, r represents rate, and t represents time. How could the formula be rearranged to determine the number of hours it takes to reach Kate's destination?
Responses
A t =

t = d r
B t =

t = r d
C t = rdt = rd
D t = drt = dr
Question 2
In the given situation, how many hours will Katie be traveling on the train?
Responses
A 5.1 hours5.1 hours
B 4.5 hours4.5 hours
C 4 hours4 hours
D 3.8 hours

1 answer

To solve these questions, let's start with the first one regarding the rearrangement of the formula \( d = rt \).

Question 1: The formula \( d = rt \) can be rearranged to solve for time (t) by isolating \( t \). To do this, divide both sides by \( r \):

\[ t = \frac{d}{r} \]

So, the correct response is: A \( t = \frac{d}{r} \)


Question 2: Now, we need to find out how many hours Katie will be traveling on the train.

Given:

  • Distance \( d = 405 \) miles
  • Rate \( r = 90 \) miles per hour

Using the formula we rearranged:

\[ t = \frac{d}{r} = \frac{405 \text{ miles}}{90 \text{ miles per hour}} \]

Calculating this:

\[ t = \frac{405}{90} = 4.5 \text{ hours} \]

Thus, the correct response is: B \( 4.5 \text{ hours} \)

In summary, for Question 1, the answer is A, and for Question 2, the answer is B.