Average of a list
There's no array here - just a handful of numbers written straight into the
expression. The mean is: add every value up, then divide by how many values
there are. Parentheses matter: without them, the division only applies to the
last number you added, not the whole sum.
The starter expression averages three small numbers - swap in this lesson's
real scores.
Your task: five quiz scores are 72, 85, 91, 68, and 80. What's the mean
(average) score?
You'll practice:
- Summing several values inside parentheses before dividing
- Why the parentheses around the sum are required, not optional
Related reading: Reading Data: Statistics That Don't Lie →