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The definition of a complement is to do with "sets". Without getting too technical, the complement of a set of things is everything of interest apart from the set of things. So if you're working with the primary colours we have Red, Green, Blue. The compliment of Red, sometimes written Redc, is Green and Blue. With percentages it's quite simple:

If 40% of a group of people have a dog, then you know 60% of those people don't have a dog. This is because everyone (100%) must either have a dog or not have a dog.

Let's say that there's still 40% of the group who own a dog, and 30% of people own a cat. It might be tempting to say that 30% have no dog or cat because 100%-30%-40% is 30%. But the problem with that logic is that some people

could have a dog AND a cat. Then you would be counting them twice. We would need to know how many people had both a dog and a cat, let's say it's 5%. So of the people, 40% have a dog. That leaves 60%. 30% have a cat. That's 30%, but 5% of the people have been counted twice, for dogs and cats. SO we need to add them back on. So 35% of people have neither a cat or a dog in this example.

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In math, a complement refers to the difference between a given quantity and 100%. To find the complement of a percent, subtract it from 100%. For example, if you have a 30% discount, the complement would be 100% - 30% = 70%, representing the remaining non-discounted amount.

Q: How do you use a complement in math with percents?

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coca

Math sucks and math sucks

I'm pretty sure u add all the percents up and divide by how many percents you added up.

Percents are used to calculate tax on EVERY store purchase,and to calculate discounts on every "special" or "bargain".If you can't calculate percents, you can't catch mistakes or avoid being cheated.

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Fractions and Percents.

coca

percents are used to dealing with math for example you can always do 45/100% wich reduces to 450%.

algebra fraction decimal ratio percents

Math sucks and math sucks

It

A waitress need to use percents to calculate his or her tip. Also, it helps to be able to add up the bill correctly.

lawyers use percents when figureing out prices and taxes of houses

I'm pretty sure u add all the percents up and divide by how many percents you added up.

What do you mean by everyday math? Everyday Math is the University of Chicago School Mathematics Project, a curriculem that many schools across America use. for more information, look it up! or do you mean everyday math as in the math we use everyday such as things like telling Tim (it is math by the way!) or handling money and finding percents for a sale price?! and multipulcation

Percents are used to calculate tax on EVERY store purchase,and to calculate discounts on every "special" or "bargain".If you can't calculate percents, you can't catch mistakes or avoid being cheated.

Percents are basically decimals, and we use decimals as numbers with extra, tiny proportions. Percents are just ways to make those decimals into a whole, more friendlier number. But, percents can also be made with decimals as well.