Katie set a goal to run 12 miles during the school week. She ran 3.42 miles on Monday and 2.7 miles on Tuesday. How many miles does Katie still need to run to reach her goal?
*
8.58 miles
9.3 miles
6.12 miles
5.88 miles
Katie ran 3.42 miles + 2.7 miles = <<3.42+2.7=6.12>>6.12 miles on Monday and Tuesday.
Therefore, Katie still needs to run 12 miles - 6.12 miles = <<12-6.12=5.88>>5.88 miles. Answer: \boxed{5.88}.
To find out how many miles Katie still needs to run to reach her goal, we need to subtract the miles she has already run from her goal of 12 miles.
Katie has run a total of 3.42 + 2.7 = 6.12 miles so far.
To find out how many miles she still needs to run, we subtract this total from her goal of 12 miles:
12 - 6.12 = 5.88 miles.
Therefore, Katie still needs to run 5.88 miles to reach her goal.