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.

Learn more about maths in brainly.com/question/22791791

6 0

2 years ago

Can anyone help me with this?

Vika [28.1K]

Answer:

x = 51

Step-by-step explanation:

The figure shown is a pentagon

The angles in a pentagon add up to equal 540

Which means that 77 + 107 + 156 + 149 + x = 540

^ ( note that we just created an equation that we can

use to solve for x )

We then solve for x using that equation

77 + 107 + 156 + 149 + x = 540

step 1 combine like terms

77 + 107 + 156 + 149 = 489

we now have 489 + x = 540

step 2 subtract 489 from each side

489 - 489 cancels out

540 - 489 = 51

we're left with x = 51

3 0

3 years ago