Topic Details (Notes format)

How to Calculate the Percentage of a Number?

Subject: Mathematics

Book: Maths Mastery

Percentages are central to countless real-world applications—from calculating exam marks to determining discounts and interest rates. The general formula to find a percentage is: (Part / Whole) × 100%. However, if you already know the rate and the whole, use Percentage of a Number = (Rate ÷ 100) × Whole. For example, to calculate 20% of 150, convert 20% to 0.20, then multiply: 0.20 × 150 = 30. This concept is pivotal in areas like finance and data analysis, so practice by computing percentages for tips in restaurants, taxes on shopping bills, or proportionate contributions in group projects. Mastering this skill builds a strong foundation for advanced percentage operations such as percentage increase, decrease, and compound interest calculations.

Practice Questions

The sides of a triangle are 5 cm, 12 cm, and 13 cm. What type of triangle is it?

View Question

What is the cube root of 729?

View Question

If x^3 - 3x^2 + 4 = 0, what is one root of the equation?

View Question

If x² - 9x + 18 = 0, what are the roots of the equation?

View Question

What is the greatest common divisor (GCD) of 36 and 48?

View Question

If the sum of the angles of a polygon is 1080°, how many sides does the polygon have?

View Question

If sin(x) = 3/5 and x is in the first quadrant, what is cos(x)?

View Question

If x^2 - 5x + 6 = 0, what are the roots?

View Question

What is the slope of a line passing through the points (2, 3) and (4, 7)?

View Question

If 2x - 3 = 7, what is the value of x?

View Question