Understanding Fractions and Percentages
Fractions: Represent parts of a whole. They have a numerator (top number) and a denominator (bottom number). For example, 1/2 represents one out of two equal parts.
Percentages: Represent parts of a whole out of 100. They are denoted by the symbol "%". For example, 50% means 50 out of 100.
Converting Between Fractions and Percentages
Example: Convert 3/4 to a percentage: * 3 ÷ 4 = 0.75 * 0.75 × 100 = 75 * Therefore, 3/4 is equal to 75%.
Example: Convert 60% to a fraction: * 60 ÷ 100 = 0.6 * 0.6 can be written as 6/10 * Simplifying the fraction gives us 3/5
Expressing Quantities as Fractions and Percentages
Example: In a class of 20 students, 12 are girls. Express the number of girls as a fraction of the class. * The whole is 20 students. * The part is 12 girls. * The fraction is 12/20, which can be simplified to 3/5.
Example: Using the previous example, express the number of girls as a percentage of the class. * We know that the fraction is 3/5. * 3 ÷ 5 = 0.6 * 0.6 × 100 = 60 * Therefore, 60% of the class are girls.
Important Notes:
Practice Problems:
3/8
Convert the following percentages to fractions:
125%
In a bag of 30 marbles, 15 are blue. Express the number of blue marbles as a fraction and a percentage of the total marbles.
These exercises will help you solidify your understanding of expressing quantities as fractions and percentages.