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Increase and Decrease an Amount by a Percent>
Increase and Decrease an Amount by a Percent 1Increase and Decrease an Amount by a Percent 1
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Question 1 of 5
1. Question
Increase `$60` by `80%`- `$` (108)
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Well Done!
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A percentage describes an amount’s relation to a whole. Dividing it by `100` converts it into a fraction.Increasing Amount by Percentage
$$\mathsf{\color{#007DDC}{new\;amount}}=\mathsf{\color{#00880A}{original}}+\mathsf{\color{#9a00c7}{increase}}$$First, solve for `80%` of the original amount, `$60`. Use fractions for easier computation.`80%times``60` `=` `80/100times60/1` Convert to fraction form `=` $$\frac{4800}{100}$$ `=` `$48` Next, use the formula to get the new amount$$\mathsf{\color{#007DDC}{new\;amount}}$$ `=` $$\mathsf{\color{#00880A}{original}}+\mathsf{\color{#9a00c7}{increase}}$$ `=` `$60` `+` `$48` `=` `$108` `$60` increased by `80%` is `$108``$108` -
Question 2 of 5
2. Question
Increase `$400` by `32%`- `$` (528)
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Nice Job!
Incorrect
A percentage describes an amount’s relation to a whole. Dividing it by `100` converts it into a fraction.Increasing Amount by Percentage
$$\mathsf{\color{#007DDC}{new\;amount}}=\mathsf{\color{#00880A}{original}}+\mathsf{\color{#9a00c7}{increase}}$$Method OneFirst, solve for `32%` of the original amount, `$400`. Use fractions for easier computation.`32%times``400` `=` `32/100times400/1` Convert to fraction form `=` `32/1times4/1` Simplify `=` $$\frac{128}{1}$$ `=` `$128` Next, use the formula to get the new amount$$\mathsf{\color{#007DDC}{new\;amount}}$$ `=` $$\mathsf{\color{#00880A}{original}}+\mathsf{\color{#9a00c7}{increase}}$$ `=` `$400` `+` `$128` `=` `$528` `$400` increased by `32%` is `$528``$528`Method TwoFirst, get the new total percentage by adding `32` to the amount’s percentage, which is `100`.`\text(Percentage)` `=` `100+32` `=` `132%` Finally, to get the percentage of an amount, simply solve for their product. Use fractions for easier computation.`132%times400` `=` `132/100times400/1` Convert to fraction form `=` `132/1times4/1` Simplify `=` $$\frac{528}{1}$$ `=` `528` `$400` increased by `32%` is `$528``$528` -
Question 3 of 5
3. Question
Increase `150 \text(km)` by `9%`Round your answer to one decimal place- (163.5) `\text(km)`
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Excellent!
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A percentage describes an amount’s relation to a whole. Dividing it by `100` converts it into a fraction.Increasing Amount by Percentage
$$\mathsf{\color{#007DDC}{new\;amount}}=\mathsf{\color{#00880A}{original}}+\mathsf{\color{#9a00c7}{increase}}$$First, solve for `9%` of the original value, `150 \text(km)`. Use fractions for easier computation.`9%times``150` `=` `9/100times150/1` Convert to fraction form `=` `9/10times15/1` Simplify `=` $$\frac{135}{10}$$ Since the value is being divided by `10`, simply move the decimal point `1` place to the left.
Hence, `9%` of `150 \text(km)` is $$\underline{\color{#9a00c7}{13.5\;\text{km}}}$$Next, use the formula to get the new amount$$\mathsf{\color{#007DDC}{new\;amount}}$$ `=` $$\mathsf{\color{#00880A}{original}}+\mathsf{\color{#9a00c7}{increase}}$$ `=` `150` `+` `13.5` `=` `163.5 \text(km)` `150 \text(km)` increased by `9%` is `163.5 \text(km)``163.5 \text(km)` -
Question 4 of 5
4. Question
Decrease `300 \text(g)` by `40%`Round your answer to one decimal place- (180) `\text(g)`
Hint
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Fantastic!
Incorrect
A percentage describes an amount’s relation to a whole. Dividing it by `100` converts it into a fraction.Decreasing Amount by Percentage
$$\mathsf{\color{#007DDC}{new\;amount}}=\mathsf{\color{#00880A}{original}}-\mathsf{\color{#9a00c7}{decrease}}$$First, solve for `40%` of the original amount, `300 \text(g)`. Use fractions for easier computation.`40%times``300` `=` `40/100times300/1` Convert to fraction form `=` `40/1times3/1` Simplify `=` $$\frac{120}{1}$$ `=` `120 \text(g)` Next, use the formula to get the new amount$$\mathsf{\color{#007DDC}{new\;amount}}$$ `=` $$\mathsf{\color{#00880A}{original}}-\mathsf{\color{#9a00c7}{decrease}}$$ `=` `300` `-` `120` `=` `180` `300 \text(g)` decreased by `40%` is `180 \text(g)``180 \text(g)` -
Question 5 of 5
5. Question
Decrease `$450` by `30%`- `$` (315)
Hint
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Keep Going!
Incorrect
A percentage describes an amount’s relation to a whole. Dividing it by `100` converts it into a fraction.Decreasing Amount by Percentage
$$\mathsf{\color{#007DDC}{new\;amount}}=\mathsf{\color{#00880A}{original}}-\mathsf{\color{#9a00c7}{decrease}}$$First, solve for `30%` of the original amount, `$450`. Use fractions for easier computation.`30%times``450` `=` `30/100times450/1` Convert to fraction form `=` `3/1times45/1` Simplify `=` $$\frac{135}{1}$$ `=` `$135` Next, use the formula to get the new amount$$\mathsf{\color{#007DDC}{new\;amount}}$$ `=` $$\mathsf{\color{#00880A}{original}}-\mathsf{\color{#9a00c7}{decrease}}$$ `=` `450` `-` `135` `=` `315` `$450` decreased by `30%` is `$315``$315`
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