Mathematics LE

Key Unit competence: Use arithmetic operations to solve simple real life problems

1.O. Introductory Activity
The simple interest earned on an investment is I prt = where I is the
interest earned, p is the principal, r, is the interest rate and t is the time in
years. Assume that 50,000Frw is invested at annual interest rate of 8%
and that the interest is added to the principal at the end of each year.
a. Discuss the amount of interest that will be earned each year for 5
years.
b. How can you find the total amount of money earned at the end of
these 5 years? Classify and explain all Mathematics operations
that can be used to find that money.

1.1 Fractions and related problems
Activity 1.1
1) Sam had 120 teddy bears in his toy store. He sold 2/3 of them at 12
Rwandan francs each. How much did he receive?
2) Simplify the following fractions and explain the method used to simplify.

3) Given that the denominator is different from zero,

4) Do you some times use fractions in your life? Explain your answer.

CONTENT SUMMARY
Consider the expressions in each of these, the numerator or
the denominator or both contain a variable or variables. These are examples
of algebraic fractions. Since the letter used in these fractions stand, for real
numbers, we deal with algebraic fractions in the same way as we do with
fractions in arithmetic. Fractions can be simplified and operations on fractions
such as addition, subtraction, multiplication and division can be applied in
simple arithmetic for solving related problems.

Adding fractions:
To add fractions there is a simple rule

Dividing fractions
To divide fractions, first flip the fraction we want to divide by, then use the
same method as for multiplication

A method of calculating the interest rate on an investment is explained in the