Question

1. Kellie and her sister Ashley are training for a marathon. Kellie ran 10 mi in 75 min. Ashley ran 15 mi in 120 min. Which statements are true? If a statement is not true, explain why. Show your work.

(a) Kellie’s minutes-per-mile pace was faster than Ashley’s minutes-per-mile pace.
(b) Kellie ran 8 mph.
(c) Ashley ran 12 mi in 90 min.

Answer 1

(a) Kellie’s minutes-per-mile pace was faster than Ashley’s minutes-per-mile pace.

True

10/75 = 0.14

15/120 = 0.13

(b) Kellie ran 8 mph.

True

10 ÷ 1.15 = 8

(c) Ashley ran 12 mi in 90 min.

False

Speed = 7.5 mph

7.5 × 1.5 = 11.25 mi

Answer 2

Explanation:

Kellie ran 10 miles in 75 minutes. This means that Kellie's speed is

10/75 = 0.1333 miles per minute.

Ashley ran 15 miles in 120 minutes. This means that Ashley's speed is

15/120 = 0.125 miles per minute.

Considering the given statements,

a) Kellie’s minutes-per-mile is

75/10 = 7.5 minutes per mile

Ashley’s minutes-per-mile pace is

120/15 = 8 minutes-per-mile

Therefore, it is true that Kellie’s minutes-per-mile pace was faster than Ashley’s minutes-per-mile pace.

b)75 minutes = 1.25 hours

Kellie's speed per hour is

10/1.25 = 8 mph

It is true

c ) Ashley's speed is

15/120 = 0.125 miles per minute. In 90 minutes, she will run

90 × 0.125 = 11.25 miles

So it is false

Ashely ran 11.25miles in 90 min.