Question

practice problems 3.1
convert the following numbers to percentages and percentages to numbers.

problem # problem

1. 3.2 =
2. 157% =
3. 20 =
4. 3.4% =
5. 0.007 =
6. 12.33% =
7. 1.40 =
8. 0.1% =
9. 4.002 =
10. 0.067% =

Explanation:

Step1: Convert decimal to percentage

To convert a number to a percentage, multiply by 100 and add the % symbol.

Step2: Convert percentage to number

To convert a percentage to a number, divide by 100 (remove the % symbol first).

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For problems 1-5 (Number to Percentage):

Problem1: Multiply by 100

$3.2 \times 100 = 320\%$

Problem2: Multiply by 100

$20 \times 100 = 2000\%$

Problem3: Multiply by 100

$0.007 \times 100 = 0.7\%$

Problem4: Multiply by 100

$1.40 \times 100 = 140\%$

Problem5: Multiply by 100

$4.002 \times 100 = 400.2\%$

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For problems 11-15 (Percentage to Number):

Problem11: Divide by 100

$\frac{157}{100} = 1.57$

Problem12: Divide by 100

$\frac{3.4}{100} = 0.034$

Problem13: Divide by 100

$\frac{12.33}{100} = 0.1233$

Problem14: Divide by 100

$\frac{0.1}{100} = 0.001$

Problem15: Divide by 100

$\frac{0.067}{100} = 0.00067$

Answer:

1. $320\%$
2. $2000\%$
3. $0.7\%$
4. $140\%$
5. $400.2\%$
6. $1.57$
7. $0.034$
8. $0.1233$
9. $0.001$
10. $0.00067$