Question

While riding her bike to the ocean and back home 5 times, Kimberly timed herself at 53min, 48min, 56min, 54min, and 45min. She had set a goal of averaging 53 minutes for her rides. How many minutes will she need to spend on her sixth ride to attain her goal?

Answer 1

Kim will need to spend 67 minutes on her sixth ride

Explanation:

Represent the number of minutes of her sixth ride by m.

Then the average number of minutes is

53 + 43 + 56 + 54 + 45 + m

---------------------------------------- = 53

6

Multiplying both sides of this equation by 6 yields

6(53 + 43 + 56 + 54 + 45 + m)

--------------------------------------------- = 6(53)

6

which simplifies to

251 + m

---------------- = 318

or 251 + m = 318. Subtract 251 from both sides to obtain the value of m:

m = 318 - 251 = 67

Kim will need to spend 67 minutes on her sixth ride to attain an average ride length of 53 minutes.i