Sierra walks her dog Pepper twice a day. Her evening walk is two and a half times as far as her morning walk which is m miles long. At the end of the week she tells her mom, "I walked Pepper for 49 miles this week!" How long is the morning walk?

morning walk is m miles long

so as per given statement

evening walk will be 2.5m miles long

total walk in a day = m + 2.5m = 3.5m miles total walk in a. week = 7 * 3.5m miles

but total walk in week is 49 miles so

7 * 3.5m = 49

dividing by 7 both side

7*3.5m / 7 = 49/7

3.5 m = 7

dividing be 3.5 both side

3.5m/3.5 = 7/3.5

m = 2

so morning walk is 2 miles long