Alex was biking along a 48 mile trail. First half of the time he was biking twice as fast as the second half of the time. If he spent 4 hours on the road, how

Question

distance = rate times time

Answer 1

We gotta make an equation out of this, so do we want the terms used to measure distance or time? Since 48 miles is a measure of distance, it would be nice if we didn't have to mess with that so let's stick to making it about distance. Let x be the speed Alex was traveling during the second half of the time....

• So for the first 2 hours, he traveled twice as fast as x (ie, a speed of 2x)
• So that's a distance of 2×2x = 4x
• For the second 2 hours, he traveled at a speed of x
• So that's a distance of 2x
• And those two distances need to add up to 48 miles

Therefore, we end up with an equation that says:

4x + 2x = 48

6x = 48

x = 8 mph traveled during the second half of the time

Your question got chopped off, but I hope this helps!

-Frank