Question

It is now 3:15 pm. Is it possible to drive 135 miles and arrive before 5:00 pm if ypu drove 55 mph? Explain your answer

Answer 1

well, how long will it take you to drive 135 miles at 55mph?

at 55 mph, you're doing 55 miles every hour, so we can simply get the quotient of 135/55 and that's how many hours it'll take you to drive 135 miles at that speed.


`\bf \cfrac{135}{55}\implies \cfrac{27}{11}\implies 2(5)/(11)~hours\implies \textit{about 2hrs, 27 minutes}`

so, it takes you that long, however, from 3:15 to 5:00pm there are only 45mins + 60mins or 1hr and 45 minutes, namely 1¾ hr.

so 2hrs and 27 minutes is much later than 1¾ hr, so, no dice, you can't arrive at 5pm, actually you'll arrive around 5:42pm.

Answer 2

From 3 pm to 5 pm is 2 hours, so you have less than 2 hours if you start at 3:15.

In two hours at 55 mph, you can drive 2×55 miles = 110 miles. It will take more than 2 hours to drive 135 miles at that speed.

Is it possible? NO
You cannot complete in less than 2 hours a trip that takes more than 2 hours to do.