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17. what is the sum of the series: 1 2/3 + 1 5/6 + 2 + + 8 1/3

18. in an arithmetic series, find the sum of the first 48 terms if the first term is -6 and the common difference is 2.

19. find the sum of the first 8 terms of the sequence: 3, -2, -7,

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 4p cubedplusx squaredequals38 comma 400. determine the rate at which sales are changing at a time when xequals80, pequals20, and the price is falling at the rate of $.20 per week.

Some boys and girls were asked if they had a pet. one third of the group were boys. there were 20 boys. 20% of the girls had a pet. boys with a pet : girls with a pet = 1 : 5 i need to know how many girls there are.

Which part of a 2-column proof is the hypothesis of the conjecture? a) given b) reasons c) prove d) statements ! i think it's b but i'm not quite