Answer:
C) +18 ÷ +3 = +6
Explanation:
The average weekly change in Alvin's training can be calculated by finding the total change in his training over the 3 weeks and then dividing it by the number of weeks. Since he reduced his training by 18 miles per week, his total change over the 3 weeks would be 18 miles/week * 3 weeks = 54 miles.
To represent the average weekly change in his training using an equation, we need to divide the total change by the number of weeks, which gives us:
Average weekly change = total change ÷ number of weeks
Substituting the values we found, we get:
Average weekly change = 54 miles ÷ 3 weeks = 18 miles/week