Learning Target:Students will learn how to write fractions and decimals as percents.
What is a percent?
If a percent is a ratio that compares a number to 100 then how could I use that fact to figure out the percent of a fraction like 17/25?
You can write an equivalent ratio to the ratio given with a denominator of 100.17/25 = 68/100 = 68%
Write the fraction as a percent.¾7/107/209/50
Write the fraction as a percent.¾ = 75/100 = 75%7/10 = 70/100 = 70%7/20 = 35/100 = 35%9/50 = 18/100 = 18%
What’s the only problem with finding the percent this way?
What’s the only problem with finding the percent this way?A: Not every denominator is going to be a factor of 100 so you there will still be times you will just have to divide the fraction to get a decimal and change it from there.
How do you write a decimal as a percent using what we know about how to write a percent as a decimal?
To write a percent as a decimal:Divide the value by 100(Move your decimal two places to the left which will make the number smaller.)
To write a decimal as a percent:Multiply the value by 100(Move your decimal two places to the right which will make the number bigger.)
But we can also write a decimal as a percent by first writing it as a fraction and then using the what we just learned to change the fraction to a percent.
Changing a decimal to a percent.0.3 = 3/103/10 = 30/10030/100 = 30%0.105 = 105/1,000105/1,000 = 10.5/10010.5/100 = 10.5%
Write the decimal as a percent.0.90.070.041
Write the decimal as a percent.0.9 = 9/10 = 90/100 = 90%0.07 = 7/100 = 7%0.041 = 41/1,000 = 4.1/100 = 4.1%
Now it is time for us to put all of our ideas together to understand the relationship between a set of numbers.
Order the numbers 2/3, 60% and 0.64 from least to greatest.What are the different ways that you could approach this problem?
Order the numbers 2/3, 60% and 0.64 from least to greatest.A: 60%, 0.64, 2/3
It would be helpful for you to recognize common percents, decimals and fractions such as the ones listed on the top of page 431.
You have attended 15 out of 20 computer classes. You must attend 85% of the classes to get a piece of software free. Do you get the software? Explain.
You have attended 15 out of 20 computer classes. You must attend 85% of the classes to get a piece of software free. Do you get the software? Explain.A: 15 / 20 = 0.75 = 75%Since 75% < 85% you do not get the software.
Can you write fractions and decimals as percents?

Sec. 8.6

  • 1.
    Learning Target:Students willlearn how to write fractions and decimals as percents.
  • 2.
    What is apercent?
  • 3.
    If a percentis a ratio that compares a number to 100 then how could I use that fact to figure out the percent of a fraction like 17/25?
  • 4.
    You can writean equivalent ratio to the ratio given with a denominator of 100.17/25 = 68/100 = 68%
  • 5.
    Write the fractionas a percent.¾7/107/209/50
  • 6.
    Write the fractionas a percent.¾ = 75/100 = 75%7/10 = 70/100 = 70%7/20 = 35/100 = 35%9/50 = 18/100 = 18%
  • 7.
    What’s the onlyproblem with finding the percent this way?
  • 8.
    What’s the onlyproblem with finding the percent this way?A: Not every denominator is going to be a factor of 100 so you there will still be times you will just have to divide the fraction to get a decimal and change it from there.
  • 9.
    How do youwrite a decimal as a percent using what we know about how to write a percent as a decimal?
  • 10.
    To write apercent as a decimal:Divide the value by 100(Move your decimal two places to the left which will make the number smaller.)
  • 11.
    To write adecimal as a percent:Multiply the value by 100(Move your decimal two places to the right which will make the number bigger.)
  • 12.
    But we canalso write a decimal as a percent by first writing it as a fraction and then using the what we just learned to change the fraction to a percent.
  • 13.
    Changing a decimalto a percent.0.3 = 3/103/10 = 30/10030/100 = 30%0.105 = 105/1,000105/1,000 = 10.5/10010.5/100 = 10.5%
  • 14.
    Write the decimalas a percent.0.90.070.041
  • 15.
    Write the decimalas a percent.0.9 = 9/10 = 90/100 = 90%0.07 = 7/100 = 7%0.041 = 41/1,000 = 4.1/100 = 4.1%
  • 16.
    Now it istime for us to put all of our ideas together to understand the relationship between a set of numbers.
  • 17.
    Order the numbers2/3, 60% and 0.64 from least to greatest.What are the different ways that you could approach this problem?
  • 18.
    Order the numbers2/3, 60% and 0.64 from least to greatest.A: 60%, 0.64, 2/3
  • 19.
    It would behelpful for you to recognize common percents, decimals and fractions such as the ones listed on the top of page 431.
  • 20.
    You have attended15 out of 20 computer classes. You must attend 85% of the classes to get a piece of software free. Do you get the software? Explain.
  • 21.
    You have attended15 out of 20 computer classes. You must attend 85% of the classes to get a piece of software free. Do you get the software? Explain.A: 15 / 20 = 0.75 = 75%Since 75% < 85% you do not get the software.
  • 22.
    Can you writefractions and decimals as percents?