Using proportions, it is found that the speed of the runners are of 16 mph and of 20 mph.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount.
After 30 minutes, the runners are 2 miles apart, hence the second runner is 4 miles per hour faster than the second, that is:
.
The first runner's speed is 4/5 of the speed of the second runner, hence:





Hence, the speed of the runners are of 16 mph and of 20 mph.
More can be learned about proportions at brainly.com/question/24863377
Hi
45. A) x
46. B) 18
47. D) 1/27
Answer:
k< or equal to 2500
Step-by-step explanation:
Answer:
12x
Explanation:
3x − 10 + 2x + 3x + x + 20 + 2x + 10 + x − 20
= 3x + −10 + 2x + 3x + x + 20 + 2x + 10 + x + −20
Combine Like Terms
= 3x + −10 + 2x + 3x + x + 20 + 2x + 10 + x + −20
= (3x + 2x + 3x + x + 2x + x) + (-10 + 20 + 10 + −20)
= 12x