Answer:
- equation: 17 +3m = 28.7
- m = 3.9
Explanation:
You want an equation and its solution to help you find the number of miles Carter must ride his bicycle each day (m) to total 28.7 miles after 3 more days, given he has already ridden 17 miles this week.
Relation
The total number of miles for the week will be 28.7. That will consist of the sum of miles already ridden (17) and the number each day multiplied by the remaining number of days.
The miles ridden each day is defined in the problem statement as "m". The number of remaining days is 3, so the total number of miles ridden on those days will be 3m.
Carter wants the sum to be ...
17 +3m = 28.7
This is the equation being asked for.
Solution
This 2-step equation is solved in the usual way:
3m = 11.7 . . . . . . . . subtract 17 from both sides
m = 3.9 . . . . . . . . . divide both sides by 3
Carter would have to ride an average of 3.9 miles each day to reach his goal.
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Additional comment
Your life experience should tell you how things add up. A total is the sum of its parts. Total miles = (miles already done) + (miles to go), for example.
Multiple things that are the same value can be "added" using multiplication: m + m + m = 3m, for example.