Answer:
3500
Explanation:
Assuming a year with 52 full weekends only, Brad will work 70 minutes for each of 50 weekends. His total time is ...
(70 min/weekend)×(50 weekends) = 3500 min
Brad volunteers 3500 minutes in one year.
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A year may have 1 or 2 extra days beyond 52 weeks, so may have 1 or 2 additional days Brad volunteers. We have assumed the case where the extra days are not ones that Brad works.