Worked examples
Two examples
Example 1
3 families have 2 children each and 2 families have 5 children each. What is the mean number of children per family?
- Total children: 3 × 2 + 2 × 5 = 16.
- Families: 3 + 2 = 5. 16 ÷ 5.
Answer: 3.2
Example 2
A class has 4 tests scored 80 and 1 test scored 100. What is the mean?
- 4 × 80 + 100 = 420, over 5 tests.
Answer: 84
Where this is taught: Quiz 38: Reading Graphs, “The weighted mean”
The drill
Ten problems
This drill also has challenge problems. They use the same skill, set up the way the GED test sometimes sets up a problem, so that it looks new at first.
How many:
Type each answer, then press Check my answers at the bottom. Commas in large numbers are fine.Write each answer on the line. The answer key, with the reasoning, is on the last page.