Question

Aneesha travels at a rate of 50 miles per hour. Morris is traveling 3 feet per second less than Aneesha. Which is the best estimate of the speed Morris is traveling?

1 mile = 5,280 feet

45 miles per hour
46 miles per hour
47 miles per hour
48 miles per hour

Answer 1

D. 48 miles per hour.

Explanation:

We have been given that Aneesha travels at a rate of 50 miles per hour.

Let us convert Annesha's speed to feet per seconds.

1 miles = 5280 feet.

50 miles = 50*5280 feet = 264000 feet.

1 minute = 60 seconds

1 hour = 60 minutes.

1 hour = 60*60 seconds = 3600 seconds.

`\text{Aneesha's speed}=\frac{264000\text{ feet}}{3600\text{ seconds}}`

`\text{Aneesha's speed}=73.333\frac{\text{ feet}}{\text{ second}}`

We are told that Morris speed is 3 feet per second less than Aneesha's speed. So let us subtract 3 from Aneesha's speed.

`\text{Morris's speed}=(73.333-3)\frac{\text{ feet}}{\text{ second}}`

`\text{Morris's speed}=70.333\frac{\text{ feet}}{\text{ second}}`

Now let us convert Morris's speed into miles per hour by multiplying his speed by 0.681818 as 1 feet per second equals 0.681818 miles per hour.

`\text{Morris's speed}=70.333*0.681818\frac{\text{ miles}}{\text{ hour}}`

`\text{Morris's speed}=47.9545326666666666439394\frac{\text{ miles}}{\text{ hour}}`

`\text{Morris's speed}\approx 48\frac{\text{ miles}}{\text{ hour}}`

Therefore, Morris is traveling at a rate of 48 miles per hour and option D is the correct choice.

Answer 2

1 mile per hour is 1 7/15 ft/s, about 1.467 ft/s, or nearly 1.5 ft/s.

Then 3 ft/s will be about 2 miles per hour. Morris's speed can be estimated at
.. 50 mph -2 mph = 48 miles per hour