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In this video, we will look at how we convert percentages to decimals.
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We will begin by recalling some basic facts about percentages and decimals.
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The word percent means out of 100.
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This means that 38 percent can be written as the fraction 38 over or out of 100.
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As the line in a fraction means divide, this is the same as 38 divided by 100.
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Dividing by 100 moves all our digits two places to the right.
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So, 38 percent is the same as 0.38.
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We can therefore say that in order to convert from a percentage to a decimal, we divide by 100.
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This means that the opposite must also be true, that to convert from a decimal to a percentage, we multiply by 100.
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In this video, we will focus on the first one of these, converting from a percentage to a decimal.
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We will now look at some questions where this is the case.
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Express 44 percent as a decimal.
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As the word percent means out of 100, we can write 44 percent as a fraction, 44 over or out of 100.
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The line in a fraction means divide, so we can write this as a decimal by dividing 44 by 100.
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This is equal to 0.44 as all the digits move two places to the right.
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44 percent expressed as a decimal is 0.44.
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To convert any percentage into a decimal, we need to divide by 100.
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We will now look at some questions in a real-life context.
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According to a recent survey, 21 percent of people prefer apples over oranges.
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Express 21 percent as a decimal.
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In order to convert from percentages to decimals, we divide by 100 as the word percent means out of 100.
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When dividing by 100, all of our digits move two places to the right.
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21 divided by 100 is therefore equal to 0.21.
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This means that 21 percent expressed as a decimal is 0.21.
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If the sales tax in a town is 2.34 percent, express the percentage as a decimal.
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We know that the word percent means out of 100.
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This means that in order to convert any percentage into a decimal, we need to divide by 100.
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In this question, we need to divide 2.34 by 100.
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As all of our digits move two places to the right, this is equal to 0.0234.
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The sales tax, 2.34 percent, expressed as a decimal is 0.0234.
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Our last couple of questions involve carrying out a calculation before converting from a percentage to a decimal.
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Mason did 32 percent of the yard work while Benjamin did 14 percent.
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Which decimal represents the amount of work they completed together?
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We’re told in the question that Mason did 32 percent of the work.
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Benjamin did 14 percent.
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To calculate the percentage they completed together, we need to add 32 percent and 14 percent.
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This is equal to 46 percent.
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Mason and Benjamin together completed 46 percent of the yard work.
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We’re asked in this question to represent this percentage as a decimal.
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To convert from a percentage to a decimal, we divide by 100.
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46 divided by 100 is 0.46.
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As 46 percent is the same as the decimal 0.46, then this represents the amount of work that Mason and Benjamin completed together.
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Our final question involves a mixture of fractions and percentages.
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In a school, 38 and one-fifth percent of students signed up to visit a local zoo.
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Express this percent as a decimal.
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There are lots of ways of approaching this problem.
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One way would be to split 38 and one-fifth percent into 38 percent and one-fifth of a percent.
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Let’s consider 38 percent first.
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As the word percent means out of 100, we know that 38 percent is equal to 38 over 100.
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This is the same as 38 divided by 100, which equals 0.38.
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This means that 38 percent is the same as the decimal 0.38.
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Let’s now consider one-fifth of a percent.
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The fraction one-fifth is the same as two-tenths.
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This is because we have multiplied the numerator and denominator by two.
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Two-tenths is the same as 0.2, as two divided by 10 is 0.2.
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We can therefore say that one-fifth of a percent is the same as 0.2 percent.
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To convert from percentages to decimals, we divide by 100.
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0.2 divided by 100 is 0.002 as all the digits move two places to the right.
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One-fifth of a percent written as a decimal is 0.002.
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Adding this to 0.38 gives us 0.382.
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38 and a fifth percent written as a decimal is 0.382.
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We will now summarize the key points from this video.
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The first thing we established was the word percent means out of 100.
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This means that 67 percent can be written as the fraction 67 over or out of 100.
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Dividing 67 by 100 gives us 0.67.
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So, 67 percent expressed as a decimal is 0.67.
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This meant that in order to convert from a percentage to a decimal, we need to divide by 100.
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As multiplying is the opposite or inverse of dividing, to convert from a decimal to a percentage, we multiply by 100.
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This means that four percent is equal to 0.04, 125 percent is equal to 1.25, and 14.8 percent is equal to 0.148.
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When dividing by 100, all of our digits move two places to the right.
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By dividing and multiplying by 100, we can convert from a percentage to a decimal and vice versa.