I need help with this question

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

26) -2(7x) = (-2 • 7) x a. associative property of addition b. associative property of multiplication c. commutative property of multiplication d. commutative property of addition

The mean of 10 values is 19. if further 5 values areincluded the mean becomes 20. what is the meanthese five additional values? a) 10b) 15c) 11d) 22