7.8333333 will be the answer
well, let's split the hours in minutes, so since 1 hr is 60 minutes, so he can walk 2.833 miles in 60 minutes, well, 3 hrs is 3*60 = 180 minutes, then we add 15 minutes, that's 195 minutes.
if he can walk 2.833 miles in 60 minutes, how long will it be for 195 minutes?

Answer: 9
Step-by-step explanation:
324: 2 2 3 3 3 3
63: 3 3 7
GCF: 3 3
The Greates Common Factor (GCF) is: 3 x 3 = 9
3.24m
the longest piece will be associated with 8 parts of the ratio.
divide 144 by 8 to find 1 part of the ration then multiply this value by 6 and 4 for the remaining parts of the ratio
= 18 cm ← 1 part
6 parts = 6 × 18 = 108 cm
4 parts = 4 × 18 = 72 cm
length = 144 + 108 + 72 = 324 cm = 3.24m