Page 46 - Mathematics

Chapter

Three Approximations

Introduction

Understanding approximations is important in our daily life. Approximations
are used in various real life situations like estimating cost of items, distances,
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and ingredients for a recipe. In this chapter, you will learn about rounding
off numbers by place values, number of decimal places and by significant
figures. Also, you will learn how to perform approximation in calculations. The
competencies developed will help you to perform real-life activities such as
estimating number of things, analysing large data, making quick calculations,
preparing budgets, and many other applications.

Meaning of approximations
Approximation is a process of finding a number that is closest to the exact value.
It involves expressing a number into a higher or lower value which is close to the
exact value. Approximation can be termed as estimation and is represented by
the symbol ̔ ≈̕.

Activity 3.1: Estimating challenge

1. In your surrounding environment (class or home), estimate the number
of objects or students available or measurements of objects.
2. Record your answers and perform actual counting or measurements and
find the difference.
3. Compare the differences you have noted between the estimated and actual
Mathematics Form One Rounding off numbers
measurement and comment on the differences.

Rounding off numbers is a process of making a number simpler, but keeping its
value closer to the original value. The outcome is less precise but more user-friendly.
Rounding off the number can be done by considering place values, number of
decimal places, and number of significant figures.

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Mathematics form 1.indd 40
Mathematics form 1.indd 40 25/10/2024 09:51:12