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PLZZ HELP: A runner, training for a competition, ran on a track every day for 10 weeks. The first week he ran 8 kilometers each day of the week. The second week he increased his daily run by one lap (400 meters). The third week he increased again his daily run by one lap and so on. What is total distance he ran in 10 weeks?

User Polo
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Answer:


Explanation:

The values in column B were found by dividing both values in column A by 10. The values in column C were found by dividing both values in column B by 2. The other columns contain multiples of the values in column B.

If we look in column E, we can see that it would take her 45 minutes to run 6 miles.

If we look in column B, we can see that she could run 2 miles in 15 minutes.

If we look in column F, we can see that she is running 8 miles every 60 minutes (which is 1 hour), so she is running 8 miles per hour.

If we look in column C, we can see that her pace is 7.5 minutes per mile.

Solution: Finding a unit rate

If we divide 150 by 20, we get the unit rate for the ratio 150 minutes for every 20 miles.

150÷20=7.5

So the runner is running 7.5 minutes per mile. We can multiply this unit rate by the number of miles:

7.5minutesmile×6 miles=45 minutes

Thus it will take her 45 minutes to run 6 miles at this pace.

If it takes her 45 minutes to run 6 miles, it will take her 45÷3=15 minutes to run 6÷3=2 miles at the same pace.

If it takes her 15 minutes to run 2 miles, it will take her 4×15=60 minutes to run 4×2=8 miles at the same pace. Since 60 minutes is 1 hour, she is running at a speed of 8 miles per hour.

We found her pace in minutes per miles in part (a).

hope it helps


User Luccas
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