Lesson 1.2 - Estimation

Estimation is a reasonable guess of a measurement; also, an approximation that results from using rounded numbers in a calculation. When using estimation, rounding numbers in your head is key. Use whole numbers in your calculations to make the mental math as easy as possible.

Example

a) Estimate the cost of two items selling for $197.00 and $73.50.

b) Estimate the perimeter of an object that has sides 11cm, 18.3 cm and 9 cm.

c) Estimate how much you would have left from $50 after purchasing a meal that cost $18.48.

Round to easy working numbers.

Remember to include the cents in your answer when answering money questions even if the cents are zero.

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Assignment 1.2 – Estimation Name: _________________

1. Estimate the cost of two items selling for $113.00 and $78.50.

2. Estimate the cost of three items selling for $19.50, $3.50 and $1.25.

3. Estimate the cost of two items selling for $22.50 and $17.99.

4. Estimate the cost of three items selling for $7.49, $1.29 and $11.77.

5. Estimate the perimeter of an object that has sides 8 cm, 11.3 cm and 19.2 cm.

6. Estimate the perimeter of an object that has sides 7.4m, 22.8m, 18.1 m and 41.35 m

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7. Estimate the cost of purchasing one of each item with the circled price on the flyer below:

8. Estimate the distance from Toronto to Oshawa given the route shown on the map:

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