How to Figure Out What Number 90 is 50% Of

Understanding Percentages: How to Figure Out What Number 90 is 50% of

Percentages are used every day to represent fractions and proportions. For example, if you see something is 50% off during a sale, you know it's now half the original price. To determine what number 90 is 50% of, you need to understand the relationship between percentages, fractions and whole numbers. Let's walk through the steps to figure out this math problem.

Reviewing Fractions

A fraction represents a part of a whole. The top number (numerator) is the number of parts you have, and the bottom number (denominator) is the total number of parts.

For example, the fraction 2/4 means you have 2 parts out of 4 total parts. Fractions that have the same numerator and denominator, like 2/2, represent the whole (100%).

Converting Fractions to Percentages

A percentage is just a fraction with a denominator of 100. To turn a fraction into a percentage, you divide the numerator by the denominator and multiply by 100.

For example, if you have a fraction of 1/2, divide 1 by 2 to get 0.5. Then multiply 0.5 by 100 to get 50%.

So the fraction 1/2 = 0.5 = 50%.

Understanding the Percent Equation

There is a reliable formula for determining what percentage one number is of another number:

Percentage = Part/Whole x 100

If you know the percentage and the part, you can plug those values into the formula to solve for the whole number.

Figuring Out What Number 90 is 50% of

Now let's apply this understanding of percentages and the percent equation to the original question: What number is 90 50% of?

We know:

• The percentage is 50%
• The part is 90

We want to find:

• The whole number

Plugging this into the percent equation:

50% = 90/Whole x 100

Now we isolate the unknown variable - the whole number:

50/100 = 90/Whole

1/2 = 90/Whole

2 = 180/Whole

Whole = 180

The Solution

Using the percent equation, we determined that 90 is 50% of 180. If you take 180 and divide it in half, you get 90.

To double check, we can take 90 and divide by the percentage (50% or 0.5) to get 180.

So 90 is 50% of 180.

Using the Percent Equation to Solve Other Percent Problems

Now that you understand how to use the percent equation, let's practice applying it to other example percentage problems:

Problem 1

25 is 10% of what number?

Percentage = 10% Part = 25 Whole = ?

Plugging into equation: 10% = 25/Whole x 100 0.10 = 25/Whole Whole = 250

Therefore, 25 is 10% of 250.

Problem 2

What number is 30% of 60?

Percentage = 30% Part = ? Whole = 60

Plugging into equation: 30% = Part/60 x 100 0.30 = Part/60 0.30 * 60 = Part Part = 18

Therefore, 30% of 60 is 18.

Problem 3

20 is 25% of what number?

Percentage = 25% Part = 20 Whole = ?

Plugging into equation: 25% = 20/Whole x 100 0.25 = 20/Whole Whole = 80

Therefore, 20 is 25% of 80.

Tips for Solving Percent Word Problems

Here are some helpful strategies for tackling other types of percent word problems:

• Draw a visual fraction to represent the percentages.
• Define the known (given) and unknown (missing) variables.
• Set up a percent equation and isolate the variable you want to solve for.
• Think logically about which number should be bigger or smaller.
• Check your solution by plugging it back into the original word problem.

Applying Percentages to Real Life Situations

Understanding percentages is an important life skill with many practical applications:

• Calculating discounts, taxes, tips, commissions, interest rates
• Comparing nutritional information on food labels
• Analyzing statistics and data
• Converting between fractions, decimals and percentages
• Scaling recipes up or down

Anytime you need to find or represent a part of a whole, percentages likely come into play. Brushing up on how to solve problems like determining what number 90 is 50% of will help boost your math abilities for daily life.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.