1. Estimation, Graphs and Mathematical Models
Lesson 1.2
Estimation, Graphs and Mathematical Models

2. Estimation – process of arriving at an approximate answer to a question
Rounding is an estimation method
Place values
, ,

3. Rounding Whole numbers
Look at digit to the right of the digit being rounded.
5 or greater round up
Less than 5 round down
This symbol ≈ means approximately equal to.

4. Round the U.S. population (311,591,917)
To the nearest million
To the nearest thousand.

5. Estimation by Rounding
You purchased bread for $2.95, detergent for $2.17, a sandwich for $3.65, an apple for $0.47 and coffee for $ The total bill was $ Is this reasonable.

6. You earn $11 an hour at a part time job.
What is your weekly salary (you work 20 hrs/ week)
What is your annual salary.

7. Pie Charts (Circle Graphs) are divided into pieces called sectors.

8. Bar graphs are convenient for showing comparisons among data

9. Line Graph – illustrate trends over time.

10. Formula – statement of equality that uses letters to express a relationship between two or more variables.
Finding Formulas to describe real-world phenomena is called mathematical modeling.

11. 6 – 30 even 43 – 52 all on pg 23