Answer:
It took Kevin 26 minutes to run from markers 1 to 4
His average speed from mile markers 1 to 4 is 0.154 miles/minute
Kevin must run by average speed 0.1 miles/minute to finish the race
Explanation:
Lets explain how to solve the problem
A half marathon 13.1 miles
Kevin took 8 minutes to run from mile marker 1 to mile marker 2 and
18 minutes to run from mile marker 2 to mile marker 4
→ He took 8 minutes and 18 minutes to run from marker 1 to marker 4
→ The total time of the first 4 marker = 8 + 18 = 26 minutes
<em>It took Kevin 26 minutes to run from markers 1 to 4</em>
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Average speed is total distance divided by total time
The average speed of Kevin as he ran from mile marker 1 to mile
marker 4 is the 4 miles divides by 26 minutes
→ Average speed = 4 ÷ 26 = = 0.154 miles/minute
<em>His average speed from mile markers 1 to 4 is 0.154 miles/minute</em>
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It took Kevin 71 minutes to pass mile marker 9
Kevin need to complete the race in 112 minutes, then what must
Kevin's average speed be as he travels from mile marker 9 to the
finish line?
The total distance of the race is 13.1 miles, he ran 9 miles
→ The remaining distance = 13.1 - 9 = 4.1 miles
He must run 4.1 miles to complete the race
The total time is 112 minutes, he used 71 minutes to run the first 9 miles
→ The remaining time = 112 - 71 = 41 minutes
He must finish the 4.1 miles in 41 minutes
→ His average speed for the last part of the race = 4.1 ÷ 41 = 0.1 mi/min
<em>Kevin must run by average speed 0.1 miles/minute to finish the race</em>
Answer:
The illumination on the book before the lamp is moved is 9 times the illumination after the lamp is moved.
Explanation:
The distance of the book before the lamp is moved,
The distance of the book after the lamp is moved,
Illumination can be given by the formula,
Illumination before the lamp is moved,
Illumination after the lamp is moved,
The illumination on the book before the lamp is moved is 9 times the illumination after the lamp is moved.