Marcus wants to know if students at his school like to sing in the shower. He polled 40 students who were not part of the school
choir. He found that 11 of the surveyed students enjoy singing in the shower. Is there a sampling bias in the situation above? A. No. Marcus selected a random, unbiased sample for his study. B. Yes. Marcus created bias by only polling 40 students. C. Yes. Marcus created bias by excluding students who are in the choir. D. There is not enough information to determine if Marcus selected a biased sample.
We know there is 57 members are in the math club and there is twice as many sixth grades than the seventh. To find out how many sixth graders are in the club, we do:
x = seventh graders 2x = sixth graders
2x + x = 3x
57=3x 57 ÷ 3 = 3x ÷3 19 = x
So there is 19 seventh graders and 19×2= 38 sixth graders
