How Do You Use Mental Math to Estimate a Percent?

Note:

Mental math is a powerful tool! See how to use mental math in this tutorial to estimate a percent!

Keywords:

problem
word problem
percent
estimate
mental math

Background Tutorials

Explain why a fraction a/b is equivalent to a fraction (n × a)/(n × b) by using visual fraction models, with attention to how the number and size of the parts differ even though the two fractions themselves are the same size. Use this principle to recognize and generate equivalent fractions.
- How Do You Write a Fraction in Simplest Form Using the GCF?
  
  When you get a fraction as an answer, you're usually asked to write it in its simplest form. This tutorial shows you how to use the GCF of the numerator and denominator to fully simplify a fraction!
- What are Equivalent Fractions?
  
  Finding equivalent fractions is an important part of things like adding, subtracting, and comparing fractions. But what are they? In this tutorial, you'll learn that equivalent fractions are just fractions that have the same value, even though they may look very different! Take a look at equivalent fractions by watching this tutorial!
Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities.
- What's a Ratio?
  
  Ratios are everywhere! The scale on a map or blueprint is a ratio. Ingredients sometimes need to be mixed using ratios such as the ratio of water to cement mix when making cement. Watch this tutorial to learn about ratios. Then think of some ratios you've encountered before!
- How Do You Write a Ratio From a Word Problem?
  
  Sometimes the hardest part of a word problem is figuring out how to turn the words into a math problem. In this tutorial, you'll see how to take the information given in a word problem and write a ratio. Then, reduce the ratio and explain its meaning. See it all in this tutorial!
Find a percent of a quantity as a rate per 100 (e.g., 30% of a quantity means 30/100 times the quantity); solve problems involving finding the whole, given a part and the percent.
- What's a Percent?
  
  Sales tax, tips at restaurants, grades on tests... no matter what you do, you can't run away from percents. So watch this tutorial and see once and for all what percents are all about!
- How Do You Turn a Decimal into a Percent?
  
  Converting decimals into percents is easier than you may think! To convert a decimal to a percent, just move the decimal point to places to the right and put a percent sign at the end! To see it done, check out this tutorial!