The answer would be 48.85
After two hours, the first car has traveled (2 x 60) = 120 miles.
That's the gap that the second car has to close.
The second car closes the gap of 120 miles in 6-2/3 hours.
He must have exceeded the first car's speed by (120/6-2/3) mph.
6-2/3 = 20/3
120 divided by 20/3 = 120 x 3/20 = 360/20 = 18 mph
The second car exceeded the first car's speed by 18 mph,
so he had to be traveling (60 + 18) = <em>78 mph</em> to catch up.
<u>Check:</u>
In 6-2/3 hours . . .
The first car covers (60 x 20/3) = <u>400</u> miles.
The second car covers (78 x 20/3) = <u>520</u> miles.
This is the same distance as the first car PLUS the 120
that he was behind when he started out.
yay !
Answer: A
explanation: 13/2= 6.5. all of the others are 2 or less therefore 13/2 is the greatest number.