Regina has a bag of 6 orange marbles and 6 black marbles. She picks a marble at random and then puts it back in the bag. She does this 24 times. The results are shown in the table.

Outcome Tally
Orange 10
Black 14
Determine the percent error of pulling a black marble in Regina’s experiment. Show your work and round your answer to the nearest hundredth.

2 answers

Since there are 6 blacks and 6 reds, the theoretical probability of pulling a black is 1/2
So in repeating this 24 times, the theoretical result should be 12 orange and 12 blacks

The actual experiment resulted in a prob of 14/24 or 7/12 of pulling a black.

There is really no "error" here, that's just how the results turned out.
If they had asked for the difference between the experimental probability and the theoretical probability, then it would be 7/12 - 1/2 = .... , now change that to a percent

Btw, your question did not state what the base of that "percent error" is, based on exp. prob.
or theor. prob.
are they right?
if so they are the 1st helpful teacher i have seen