This math topic focuses on advanced problems related to calculating the mean of a set when a value is missing. Practicing skills include determining what number should replace the missing value (denoted as '?') in a series to achieve the specified average. Each problem provides a series of numbers with one value missing and a stated mean. Students must use their understanding of mean calculation to find the correct missing number from multiple choices provided. This involves multiplying, adding, and reasoning to back-calculate the missing value that results in the given mean.
Work on practice problems directly here, or download the printable pdf worksheet to practice offline.
Complete these online problems with 80% or 4 correct answers in a row. Results are immediate.
What is the missing number that results in these numbers having the given mean
?, 6, 20, 1, 15
mean = 11