Nikita ran a 5-kilometer race in 39 minutes (0.65 of an hour) without training beforehand. In the first part of the race, her av
erage speed was 8.75 kilometers per hour. For the second part of the race, she started to get tired, so her average speed dropped to 6 kilometers per hour. Which expression represents Nikita’s distance for the second part of the race?
Nikita's distance from her for the second part of the race was 1.5 kilometers.
Since Nikita ran a 5-kilometer race in 39 minutes (0.65 of an hour) without training beforehand, and in the first part of the race, her average speed was 8.75 kilometers per hour, while for the second part of the race, she started to get tired, so her average speed dropped to 6 kilometers per hour, to determine which expression represents Nikita's distance for the second part of the race the following calculation must be performed:
8.75 x 0.65 + 6 x 0 = 5.68
8.75 x 0.50 + 6 x 0.15 = 5.275
8.75 x 0.40 + 6 x 0.25 = 5
100 = 60
40 = X
40 x 60/100 = X
24 = X
39 - 24 = 15
15 = 1/4 hour
6/4 = 1.5
Therefore, Nikita's distance from her for the second part of the race was 1.5 kilometers.
