Question

Two cars leave Phoenix and travel along roads 90 degrees apart. If Car 1 leaves 30 minutes earlier than Car 2 and averages 42 mph and if Car 2 averages 50 mph, how far apart will they be after Car 1 has traveled 3.5 hours?
A: 230
B: 250
C: 210

Answer 1

Answer:

C. 210 miles

Step-by-step explanation:

We have been given that two cars leave Phoenix and travel along roads 90 degrees apart. Car 1 leaves 30 minutes earlier than Car 2 and averages 42 mph.

We will use distance formula and Pythagoras theorem to solve our given problem.

$\text{Distance}=\text{Speed}\times \text{Time}$

$\text{Distance covered by Car 1 in 3.5 hours}=\frac{42\text{ Miles}}{\text{Hour}}\times \text{3.5 hour}$

$\text{Distance covered by Car 1 in 3.5 hours}=147\text{ Miles}$.

Since car 1 leaves 30 minutes before car 2, so car 2 will travel for only 3 hours when car 1 will travel for 3.5 hours.

$\text{Distance covered by Car 2 in 3 hours}=\frac{50\text{ Miles}}{\text{Hour}}\times \text{3 hour}$

$\text{Distance covered by Car 2 in 3 hours}=150\text{ Miles}$

Since both car travel along roads 90 degree apart, therefore, the distance between both cars after Car 1 has traveled 3.5 hours would be hypotenuse with legs 147 and 150.

$\text{Distance between both cars}=\sqrt{147^2+150^2}$

$\text{Distance between both cars}=\sqrt{21609+22500}$

$\text{Distance between both cars}=\sqrt{44109}$

$\text{Distance between both cars}=210.021427\approx 210$

Therefore, the both cars will be 210 miles apart and option C is the correct choice.