Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Understanding Tenths: When a whole object or group is divided into 10 equal parts, each part is called one-tenth. In fraction form, it is written as and in decimal form as . Visually, imagine a long chocolate bar divided into 10 equal vertical slices; eating one slice means you ate of the bar.
Understanding Hundredths: When a whole is divided into 100 equal parts, each part is one-hundredth. This is written as or . If you look at a large square grid containing 100 small squares (), shading just one tiny square represents of the whole grid.
The Decimal Point: The decimal point is a dot used to separate the whole number part from the fractional part. For example, in , is the whole number, and represents tenths and hundredths.
Converting Tenths to Decimals: To convert a fraction with a denominator of to a decimal, we write the numerator and place the decimal point one digit from the right. For example, . If the fraction is , it becomes .
Converting Hundredths to Decimals: To convert a fraction with a denominator of , we place the decimal point two digits from the right. For example, . If the numerator has only one digit, like , we add a zero to the left of the digit to keep the place value, resulting in .
Place Value Chart: Decimals follow a specific place value system. To the left of the decimal are Ones, Tens, and Hundreds. To the right are Tenths () and Hundredths (). In the number , the digit is in the tenths place and is in the hundredths place.
Equivalent Decimals: Adding zeros to the right of a decimal number does not change its value. For instance, is equal to . Visually, shading out of columns in a grid is the exact same total area as shading out of small squares.
Money and Decimals: In the Indian currency system, Rupee = Paise. Therefore, Paisa = Rupee = . This makes money a perfect real-world example of the hundredths place value.
📐Formulae
💡Examples
Problem 1:
Convert the following fractions into decimals: (a) (b) (c)
Solution:
(a) (One zero in denominator means one decimal place). (b) (Two zeros in denominator mean two decimal places). (c) (The whole number stays to the left of the point).
Explanation:
To convert fractions with denominators of 10 or 100, count the number of zeros in the denominator and place the decimal point that many places from the right of the numerator.
Problem 2:
Convert and into fractions in their simplest form.
Solution:
- For : It has one decimal place, so the denominator is . Fraction = . Simplified: .
- For : It has two decimal places, so the denominator is . Fraction = . Simplified: .
Explanation:
The number of digits after the decimal point determines if the denominator is 10 or 100. Once the fraction is written, divide both numerator and denominator by their highest common factor to simplify.