Question

A runner ran 2/3 of a 5 kilometer race in 21 minutes. They ran the entire race at a constant speed.

Answer 1

A)
distance covered 
5*2/3 = 3.333
time taken = 21min
this means  it takes 
5*6.306 = 31.53 to covers 5 km
b) 21min/3.33 = 6.306 time taken  to ran 1 km

Answer 2

Answer:

it take 31.53 minutes to run the entire race

it take 6.3 minutes to run the 1 km

Step-by-step explanation:

A runner ran 2/3 of a 5 kilometer race in 21 minutes. They ran the entire race at a constant speed.

$\frac{2}{3} \cdot 5= \frac{10}{3}$

3.33 km is covered in 21 minutes

So 5 km is covered in $\frac{5 \cdot 21}{3.33}=31.53$minutes

it take 31.53 minutes to run the entire race

$\frac{10}{3}$ km is covered in 21 minutes

1 km is covered in $\frac{21}{\frac{10}{3} } =6.3$