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Daniel Math Academy · Grade 7 Math

Make Estimates from Samples

Skill N.9 · Statistics & sampling · ★★☆ Medium

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Write a proportion and solve it.

1. 1
   In a random sample of $80$ voters in a town, $11$ support building a new library. The town has $2,000$ voters. Estimate how many voters support the new library.
2. 2
   In a random sample of $40$ voters in a town, $7$ support building a new library. The town has $4,000$ voters. Estimate how many voters support the new library.
3. 3
   Ms. Reed picked $20$ seventh graders at random, and $8$ of them ride a bus to school. There are $540$ seventh graders in all. About how many ride a bus?
4. 4
   A factory checks a random sample of $400$ light bulbs and finds $2$ that do not work. Predict how many of the $4,000$ bulbs it made today do not work.

Daniel Math Academy · Grade 7 Math

Answer Key

N.9 Make Estimates from Samples · ★★☆ Medium

1. 1275 voters
2. 2700 voters
3. 3216 students
4. 420 bulbs