We have been given that a colleague has been tutoring six students in 11th grade to prepare for the ACT. Student scores were as follows: 20, 18, 16, 15, 23, 20. We are asked to find the mean of the ACT scores.
We will use mean formula to solve our given problem.
Upon rounding to nearest whole number, we will get:
Therefore, the mean of the ACT scores is 19 and option 'c' is the correct choice.