Keisha ran 2.4 miles more than Jamal.
Keisha ran 8.5 miles, how many miles did Jamal run?
m = the number of miles Jamal ran
2.4 + m = 8.5
[Keisha ran 2.4 more miles than Jamal(m), she ran a total of 8.5 miles]
2.4 + m = 8.5 Subtract 2.4 on both sides
m = 6.1
Jamal ran 6.1 miles (Your answer is the 2nd option)