Question

1. kofi plans to run 30 miles this week. he wants to run the same number of miles each day of the week. he says he will run $\frac{7}{30}$ mile each day. is he correct? explain.
2. jiro and his big brother ride an elevator 8 floors up to their apartment. the ride takes 42 seconds, and the elevator makes no stops on the way. suppose the elevator takes the same amount of time to go up each floor. how many seconds does it take the elevator to go up each floor? show your work.

Explanation:

Step1: (For Question 4) Check total miles

Total miles if Kofi runs $\frac{7}{30}$ mile per day for 7 days:
$\frac{7}{30} \times 7 = \frac{49}{30} = 1\frac{19}{30}$ miles

Step2: (For Question 4) Compare to target

Target total miles = 30 miles. $\frac{49}{30}
eq 30$
Correct daily distance: $\frac{30}{7}$ miles per day

Step3: (For Question 5) Calculate per-floor time

Total time = 42 seconds, floors = 8.
Time per floor: $\frac{42}{8} = 5.25$ seconds

Answer:

Question 4:

Kofi is not correct. If he runs $\frac{7}{30}$ mile each day for 7 days, he only runs $\frac{49}{30}$ miles total, which is much less than his 30-mile goal. To run 30 miles in 7 days, he needs to run $\frac{30}{7}$ miles per day.

Question 5:

5.25 seconds