Reviewed by Janice S. Armas
What is 10% of 40?
Answer: 10% of 40 is 4
Finding a certain percentage of a number is a fundamental math skill, often used in situations like calculating discounts, interest, or portions. In this case, we're asked to find what 10% of 40 is. Percentages represent parts per hundred, so 10% simply means 10 out of every 100, or one-tenth.
Methods
Math Tutor Explanation Using the Percentage Formula
You can calculate a percentage of a number by multiplying the number by the percentage (expressed as a decimal).
Step 1: Step 1: Convert the percentage to a decimal by dividing by 100 (10% becomes 0.10)
Step 2: Step 2: Multiply the decimal by the number (0.10 × 40)
Math Tutor Explanation Using Proportion Method
Alternatively, you can set up a simple proportion to find what 10% of 40 is.
Step 1: Step 1: Write a proportion: 10/100 = x/40
Step 2: Step 2: Solve for x by cross multiplying, resulting in x = (10 × 40) / 100
Step 1:
Step 2:
Math Tutor suggests: Practice More Percentage Calculations
Continue building your skills in calculating percentages with these similar questions and real-world examples.
FAQ on Calculating Percentages
How do I convert a percentage to a decimal?
Divide the percentage number by 100. For example, 10% becomes 0.10.
Why do we multiply after converting to decimal?
Multiplying applies the percentage as a fraction of the original number to find the part represented.
Can I use a calculator for these problems?
Yes, using a calculator can speed up calculations, especially for larger or more complex percentages.
How would I mentally calculate 10% of any number?
Simply move the decimal point one place to the left. For example, 10% of 50 is 5.0.
Math & reading from 1st to 9th grade
Looking for homework support for your child?
Choose kid's grade
