Worked examples
Two examples
Example 1
You roll a number cube 60 times. About how many 3s should you expect?
- P(3) = 16. 16 × 60.
Answer: 10
Example 2
5% of parts are faulty. In 400 parts, about how many are faulty?
- 0.05 × 400.
Answer: 20
Where this is taught: Quiz 34: Probability and Counting, “The same thing, bigger”
The drill
Ten problems
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.