Question

David decided to go to the beach, so he jumped into his car and drove an average speed of 40 miles per hour. David's sister Liz also wanted to go, but she had to wait until her favorite TV show ended. Liz left 12 minutes after David. If Liz drives at an average speed of 55 miles per hour, how far away from their home will she pass David? Round to the nearest answer.

A.) 1760 miles
B.) 29 miles
C.) 40 miles
D.) Liz will never pass David.

Answer 1

Answer: Option 'B' is correct.

Step-by-step explanation:

Since we have given that

Average speed of David = 40 mph

Average speed of Liz = 55 mph

According to question, it is given that Liz left 12 minutes after David.

Let the distance away from their home be x

So, it becomes,

`(x)/(40)-(x)/(55)=(12)/(60)\\\\(11x-8x)/(440)=(1)/(5)\\\\(3x)/(440)=(1)/(5)\\\\x=(1)/(5)* (440)/(3)=(88)/(3)=29.33\ miles`

She will pass David after 29 miles.

Hence, Option 'B' is correct.