A Question And Interest - Sharp EL-531RH Teachers Manual

A Question of Interest
• • • • • • • • • • • • • • • • • • • • • Objective • • • • • • • • • • • • • • • • • • • • •
Understand, use and calculate with percentages.
Select suitable sequences of operations and methods of computation, including trial-and-improve-
ment methods, to solve problems involving integers, decimals and percentages.
Give solutions in the context of the problem, selecting an appropriate degree of accuracy, and
interpret the display on a calculator.
• • • • • • • • • • • • • • • Explanation of the activity • • • • • • • • • • • • • •
Use the calculator to find solutions to problems involving interest rates.
While working on this activity, students will develop their understanding of percentages within the
context of compound interest situations.
• • • • • • • • • • • • • • • • • Using the calculator • • • • • • • • • • • • • • • • •
Press the following buttons and then start operation.
If you invest money at a certain level of interest, by how much will your money grow?
Example:
$100 is invested at 0.1% annual interest.
Using multiplication: Multiply the principal $100 by 1.001.
100 1.001
For the total after two years, multiply the previous answer
again by .00 .
1 1
1.001
After three years...
After four years...
After 10 years, you have approximately $101.
Calculator functions used: % calculation, multiplication
100X1.001=
ANSX1.001=
ANSX1.001=
ANSX1.001=
ANSX1.001=
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Junior high school
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