The Briarwood Middle School Chess club has 75 members. Of those members, 15 are 7th graders. What percent of the chess club members are not 7th graders? (Proportional Reasoning)

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Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.

The table below shows the approximate height of an object x seconds after the object was dropped. the function h(x)= -16x^2 +100 models the data in the table. for which value of x would this model make it the least sense to use? a. -2.75 b. 0.25 c. 1.75 d. 2.25

Math question.. plz me .. best answer all