at a school carnival, a large jar has been filled with marbles. all the marbles are either red or blue. the…

at a school carnival, a large jar has been filled with marbles. all the marbles are either red or blue. the school is offering a prize for correctly guessing the percentage of blue marbles in the jar. students are allowed to pick a sample of 10 marbles to help them guess. the sample marbles are returned to the jar after each sample, and the marbles are remixed. the results of the first 20 samples are shown in the dot - plot. number of blue marbles out of 10 based on the samples, which would be the best guess for the percentage of blue marbles in the jar? a 65% b 55% c 35% d 15%

at a school carnival, a large jar has been filled with marbles. all the marbles are either red or blue. the school is offering a prize for correctly guessing the percentage of blue marbles in the jar. students are allowed to pick a sample of 10 marbles to help them guess. the sample marbles are returned to the jar after each sample, and the marbles are remixed. the results of the first 20 samples are shown in the dot - plot. number of blue marbles out of 10 based on the samples, which would be the best guess for the percentage of blue marbles in the jar? a 65% b 55% c 35% d 15%

Answer

Explanation:

Step1: Calculate the total number of blue - marbles in all samples

We count the number of dots for each value of the number of blue marbles out of 10 and multiply by that value, then sum them up. For 1 blue marble: 2 dots, so (1\times2 = 2) For 2 blue marbles: 4 dots, so (2\times4=8) For 3 blue marbles: 6 dots, so (3\times6 = 18) For 4 blue marbles: 4 dots, so (4\times4=16) For 5 blue marbles: 2 dots, so (5\times2 = 10) For 6 blue marbles: 1 dot, so (6\times1=6) For 7 blue marbles: 1 dot, so (7\times1 = 7) The sum is (2 + 8+18+16+10+6+7=67)

Step2: Calculate the total number of marbles sampled

Since each sample has 10 marbles and there are 20 samples, the total number of marbles sampled is (10\times20 = 200)

Step3: Calculate the percentage of blue marbles

The percentage of blue marbles is (\frac{67}{200}\times100%=33.5%\approx35%)

Answer:

C. 35%