Question

How much time will it take Jenny to bike 15 miles if she bikes at a speed of 6 mph?

Answer 1

this lesson, we will investigate the relationship between the distance traveled, the rate or speed or travel, and the time that it takes to travel that distance at that rate. We will also look at a few other related products.

Distance = (Rate)(Time)

The equation that relates distance, rate, and time is

d = rt

Where d is the distance traveled, r is the rate, and t is the time. On the CAHSEE exam, you will be given two of these and will be asked to use the above equation to find

• took Markus half an hour to drive home from work. He averaged 34 miles per hour. How far does Markus live from his work?
• Solution
• We are given that it takes 1/2 an hour for the trip. This is a time:
• t = 1/2
• We are given that he averages 34 miles per hour. This is a rate:
• r = 34
• We are asked how few he has traveled. This is a distance. We use the d=rt equation:
• d = rt
• = (34)(1/2)
• = 17

Answer 2

2.5 hours

Explanation:

First, try rewriting Jenny's speed in it's fraction form: 6 mi/hr

Next, use the units to set up an equation that relates Jenny's speed to the distance they want to travel. Let's call the unknown time t:

6mi/hr=15mi/t

1/t=6/15 (mi/hr•1/mi)

t=15/6 (hrs/mi•mi)= 15/6 (hrs•mi/mi)= 15/6 hrs

t=2.5hrs

So it'd take Jenny 2.5hrs at 6mph to go 15 miles. The key here is to keep track of the units. You can treat them like fractions and reduce them away as if they were numbers or variables.