Grade Level: 6th Skill: Reasoning Topic: Are Your Results Reasonable? Goal: Use estimation to verify the reasonableness of calculated results. Skill Description: Round numbers in a given problem and use to calculate an estimate. Compare an estimate to a solution to check for reasonableness of a result. Make estimations to check: whole number, fraction and decimal calculations involving addition, subtraction, multiplication and division.

## Building Blocks/Prerequisites

### Sample Problems

 (1) Solve the problem. Estimate to check. 39 + 73 (112, Estimate: 40 + 70 = 110) (2) Solve the problem. Estimate to check. 55.95 – 12.43 (43.52, Estimate: 56 – 12 = 44) (3) Solve the problem. Estimate to check. 4 ¼ x 5 ¾ (24 11/12, Estimate: 4 x 6 = 24) (4) Tiffany bought 5 friends movie passes. Each pass was \$4.95. How much did Tiffany spend? Estimate to check. (\$24.75, Estimate: 5 x 5 = 25) (5) Randy’s family went to the movies. They bought two adult tickets for \$8.50 and three children’s tickets for \$5.75. How much money did they spend in all? Estimate to check and explain why your answer is reasonable. (\$34.25, Estimate: 2 X 9 = 18, 6 x 3 = 18, 18 + 18 = 32. My answer is reasonable because my estimate of 32 is fairly close to \$34.25.)

### Online Resources

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