percent proportion equation solve practical problems using proportional reasoning
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Percent Proportion Percent Proportion EquationEquation
Solve practical problems Solve practical problems using proportional reasoningusing proportional reasoning
Percent: a number over 100Percent: a number over 100
Express the percent as a fraction and Express the percent as a fraction and as a decimal.as a decimal.
65 65 % % 665 5
%%
FractioFractionn
10100 0
55
55 220 0
113 3 ==
Fractions needs to Fractions needs to
be written in be written in simplest form, if simplest form, if
it’s possibleit’s possible
DecimDecimalal 6 5 6 5
%%
..
Move the decimal Move the decimal point two places to point two places to
the left, then remove the left, then remove the symbolthe symbol
0 0
Percent: a number over 100Percent: a number over 100
Express the percent as a fraction and Express the percent as a fraction and as a decimal.as a decimal.
125 125 % % 12125 5
%%
FractioFractionn
10100 0
2525
25254 4 5 5 ==
Fractions needs to Fractions needs to
be written in be written in simplest form, if simplest form, if
it’s possibleit’s possible
DecimDecimalal 1 2 1 2 5 5
%%
..
Move the decimal Move the decimal point two places to point two places to
the left, then remove the left, then remove the symbolthe symbol
Percent: a number over 100Percent: a number over 100
Express the fraction as a percent.Express the fraction as a percent.
FractioFractionn
220 0
3 3
PercentPercent x5x5 x5x5 1010
0 0
115 5 = = 115 5 10100 0
%%
Percent: a number over 100Percent: a number over 100
Express the decimal as a percent.Express the decimal as a percent.
0.125 0.125
DecimDecimalal
PercePercentnt
1 2 1 2 5 5
%%
..
Move the decimal Move the decimal point two places to point two places to
the right, then add the the right, then add the % symbol% symbol
0 0
Percent: a number over 100Percent: a number over 100
Express the decimal as a percent.Express the decimal as a percent.
3.12 3.12
DecimDecimalal
PercePercentnt
1 2 1 2 %%
..
Move the decimal Move the decimal point two places to point two places to
the right, then add the the right, then add the % symbol% symbol
3 3
In a percent proportion equation, the numerator called the is is , is being compared to the whole quantity called of of . The other ratio is the percent written as a numbernumber, whose base is 100100
Percent Percent proportionproportion
““isis over over ofof equals equals percentpercent over over 100100.”.”
100
%
of
is
Many word problems can be solved using the formula
Percent Percent proportionproportion
The value of the is & of come from the problem
The number here is already a percent, just replace with the number
The 100 stays the same in all problems
Percent Percent proportionproportion
4 is 50% of 4 is 50% of 88 isis
ofof%%
100100==44
885050
10 is 20% of 10 is 20% of 5050 isis
ofof%%
100100==1010
50502020
Percent Percent proportionproportionWhat number is 5% of What number is 5% of
40?40?isisofof
%%100100
==xx
404055
100100==xx
404055
Use cross Use cross product product to solve to solve the the proportioproportionn100 x = 5 100 x = 5
4040
Solve the Solve the equation equation by doing by doing the the oppositeopposite100 x = 100 x =
200200100 100 100100x = x =
225% of 40 is 5% of 40 is 22
Write a Write a sentence as sentence as an answeran answer
Percent Percent proportionproportion72 is 6% of what 72 is 6% of what number?number?isisofof
%%100100
==7272
xx66
100100==7272
xx66
Use cross Use cross product product to solve to solve the the proportioproportionn6 x = 72 6 x = 72
100100
Solve the Solve the equation equation by doing by doing the the oppositeopposite 6 x = 6 x =
72007200 6 66 6x = x = 1,2001,200
72 is 6% of 72 is 6% of 1,2001,200
Write a Write a sentence as sentence as an answeran answer
Percent Percent proportionproportion8 is what percent of 8 is what percent of
40?40?isisofof
%%100100
==88
4040xx
100100==88
4040xx
Use cross Use cross product product to solve to solve the the proportioproportionn40 x = 8 40 x = 8
100100
Solve the Solve the equation equation by doing by doing the the oppositeopposite 40 x = 40 x =
800800 40 40 4040x = x = 2020
8 is 20% of 8 is 20% of 4040
Write a Write a sentence as sentence as an answeran answer
Practice Percent Practice Percent proportionproportion50 is 20% of what 50 is 20% of what numbernumber
isisofof
%%100100
==5050
xx2020
What number is What number is 45% of 18045% of 180
isisofof
%%100100
==xx
1801804545
20 x = 50 20 x = 50 100100 20 x = 20 x = 50005000 20 2020 20
x = 250x = 250
100 x = 45 100 x = 45 180180100 x = 100 x = 81008100100 100 100100x = x =
8181
You try!
Practice Percent Practice Percent proportionproportionWhat percent of 90 is What percent of 90 is 36?36?
isisofof
%%100100
==3636
9090xx
What percent of What percent of 185 is 35185 is 35
isisofof
%%100100
==3535
185185xx
90 x = 36 90 x = 36 100100 90 x = 90 x = 36003600 90 90 9090x = x =
4040
185 x = 35 185 x = 35 100100185 x = 185 x = 35003500185 185 185185x = x =
18.918.9
Percent Percent proportionproportionMateo answer 20 question out of 25 in his Mateo answer 20 question out of 25 in his Math test. What percent of the test does he Math test. What percent of the test does he answer correctly?answer correctly?
isisofof
%%100100
==2020
2525xx
100100==2020
2525xx
Use cross Use cross product product to solve to solve the the proportioproportionn25 x =20 25 x =20
100100
Solve the Solve the equation equation by doing by doing the the oppositeopposite 25 x = 25 x =
20002000 25 25 2525x = x = 8080
He answered He answered 80% of the 80% of the
test test correctly.correctly.
Write a Write a sentence as sentence as an answeran answer
Percent Percent proportionproportionThere are 300 students in 7There are 300 students in 7thth grade, 30% grade, 30% are in Mr. Montoya’s class. How many are in Mr. Montoya’s class. How many students are in his class?students are in his class?
isisofof
%%100100
==xx300300
3030100100
==xx
3003003030
Use cross Use cross product product to solve to solve the the proportioproportionn100x =30 100x =30
300300
Solve the Solve the equation equation by doing by doing the the oppositeopposite100 x = 100 x =
90009000 100 100 100100x = x = 9090
He has 90 He has 90 students in students in his class.his class.
Write a Write a sentence as sentence as an answeran answer
Percent Percent proportionproportionA serving of ice cream contains 240 calories. A serving of ice cream contains 240 calories. 144 calories comes from fat. What percent 144 calories comes from fat. What percent of the total calories comes from fat ?of the total calories comes from fat ?
isis
ofof%%
100100==144144
240240xx
100100==144144
240240xx
Use cross Use cross product product to solve to solve the the proportioproportionn240x =144 240x =144
100100
Solve the Solve the equation equation by doing by doing the the oppositeopposite 240 x = 240 x =
1440014400 240 240 240240x = x = 6060
60% of the 60% of the calories calories
comes from comes from fat.fat.
Write a Write a sentence as sentence as an answeran answer
Percent Percent proportionproportionMrs. Finnegan has a large container of olive oil. Mrs. Finnegan has a large container of olive oil. She has used 2 quarts of oil, seventy-five percent She has used 2 quarts of oil, seventy-five percent of the olive oil remains. How many quarts of oil of the olive oil remains. How many quarts of oil remains ?remains ?
isisofof
%%100100
==22xx
2525100100
==22
xx2525
Use cross Use cross product product to solve to solve the the proportioproportionn 25x =2 25x =2
100100
Solve the Solve the equation equation by doing by doing the the oppositeopposite 25 x = 20025 x = 200
25 2525 25x = x = 88
She has 8 She has 8 more quarts more quarts of olive oil.of olive oil.
Write a Write a sentence as sentence as an answeran answer