Decimal place value: Count decimal places, write as fraction, simplify to lowest terms.
- Count decimal places
- Write decimal digits as numerator over appropriate power of 10
- Find GCD of numerator and denominator
- Divide both by GCD to get simplest form
- Verify by dividing numerator by denominator
Decimal places: 1 → denominator = 10
0.4 = 4/10
GCD(4,10) = 2
4÷2 = 2, 10÷2 = 5
So 0.4 = 2/5
Decimal places: 2 → denominator = 100
0.75 = 75/100
GCD(75,100) = 25
75÷25 = 3, 100÷25 = 4
So 0.75 = 3/4
Decimal places: 1 → denominator = 10
0.2 = 2/10
GCD(2,10) = 2
2÷2 = 1, 10÷2 = 5
So 0.2 = 1/5
Decimal places: 1 → denominator = 10
0.5 = 5/10
GCD(5,10) = 5
5÷5 = 1, 10÷5 = 2
So 0.5 = 1/2
Decimal places: 3 → denominator = 1000
0.125 = 125/1000
GCD(125,1000) = 125
125÷125 = 1, 1000÷125 = 8
So 0.125 = 1/8
Decimal places: 3 → denominator = 1000
0.875 = 875/1000
GCD(875,1000) = 125
875÷125 = 7, 1000÷125 = 8
So 0.875 = 7/8
Decimal places: 2 → denominator = 100
0.04 = 4/100
GCD(4,100) = 4
4÷4 = 1, 100÷4 = 25
So 0.04 = 1/25
Decimal places: 3 → denominator = 1000
0.625 = 625/1000
GCD(625,1000) = 125
625÷125 = 5, 1000÷125 = 8
So 0.625 = 5/8
Separate: 2 + 0.25
Convert decimal part: 0.25 = 25/100 = 1/4
Combine: 2 + 1/4 = 2 1/4
Decimal places: 3 → denominator = 1000
0.008 = 8/1000
GCD(8,1000) = 8
8÷8 = 1, 1000÷8 = 125
So 0.008 = 1/125
Decimal places: 3 → denominator = 1000
0.375 = 375/1000
GCD(375,1000) = 125
375÷125 = 3, 1000÷125 = 8
So 0.375 = 3/8
Decimal places: 2 → denominator = 100
0.06 = 6/100
GCD(6,100) = 2
6÷2 = 3, 100÷2 = 50
So 0.06 = 3/50
Separate: 3 + 0.5
Convert decimal part: 0.5 = 5/10 = 1/2
Combine: 3 + 1/2 = 3 1/2
Decimal places: 3 → denominator = 1000
0.001 = 1/1000 (already in simplest form)
Separate: 1 + 0.125
Convert decimal part: 0.125 = 125/1000 = 1/8
Combine: 1 + 1/8 = 1 1/8
1. 0.4 = 2/5
2. 0.75 = 3/4
3. 0.2 = 1/5
4. 0.5 = 1/2
5. 0.125 = 1/8
6. 0.875 = 7/8
7. 0.04 = 1/25
8. 0.625 = 5/8
9. 2.25 = 2 1/4
10. 0.008 = 1/125
11. 0.375 = 3/8
12. 0.06 = 3/50
13. 3.5 = 3 1/2
14. 0.001 = 1/1000
15. 1.125 = 1 1/8
Decimal: A number that uses a decimal point to separate the whole number part from the fractional part
Fraction: A number representing a part of a whole, expressed as numerator/denominator
Place Value: The value of a digit based on its position in a number
Simplest Form: A fraction reduced to lowest terms where numerator and denominator have no common factors except 1
GCD (Greatest Common Divisor): The largest number that divides both numerator and denominator evenly
- Analyze the decimal: Count how many digits are after the decimal point
- Identify the place value: Determine if it's tenths, hundredths, thousandths, etc.
- Write the fraction: Use the digits as numerator, denominator based on place value
- Simplify: Reduce to lowest terms by dividing by GCD
- Verify: Divide numerator by denominator to check accuracy
• n decimal places → denominator = 10^n
• Simplification: Divide by GCD(numerator, denominator)
• Verification: numerator ÷ denominator should equal original decimal
• Mixed number: Whole part + (decimal part converted to fraction)
A1. 0.0001 = 1/10000
A2. 4.0625 = 4 1/16
A3. 0.016 = 2/125
A4. 0.1875 = 3/16
A5. 5.005 = 5 1/200
A6. 0.003 = 3/1000
A7. 0.0005 = 1/2000
A8. 6.125 = 6 1/8
Sarah ate 0.75 of a pizza. What fraction of the pizza did she eat?
0.75 = 75/100 = 3/4
Answer: Sarah ate 3/4 of the pizza.
Tom walked 2.5 miles to school. Express this distance as a mixed number.
2.5 = 2 + 0.5 = 2 + 5/10 = 2 + 1/2 = 2 1/2
Answer: Tom walked 2 1/2 miles.
Anna spent $0.25 on candy. What fraction of a dollar did she spend?
0.25 = 25/100 = 1/4
Answer: Anna spent 1/4 of a dollar.
Decimal Place Value: Each position after the decimal point represents a specific fraction of 1
Tenths: 1 decimal place (0.1 = 1/10)
Hundredths: 2 decimal places (0.01 = 1/100)
Thousandths: 3 decimal places (0.001 = 1/1000)
Ten-Thousandths: 4 decimal places (0.0001 = 1/10000)
Hundred-Thousandths: 5 decimal places (0.00001 = 1/100000)
- Count decimal places: Determine how many digits come after the decimal point
- Write initial fraction: Use decimal digits as numerator, denominator as 10^places
- Find GCD: Greatest Common Divisor of numerator and denominator
- Divide both parts: by GCD to get simplest form
- Verify result: Divide numerator by denominator to confirm
• n decimal places → denominator = 10^n
• Always express in simplest form by dividing by GCD
• For mixed numbers, convert decimal part separately
• Leading zeros count in decimal places: 0.05 has 2 places
• Verify by dividing numerator by denominator
Visual Conversion Guide
0.1 = One Tenth = 1/10
0.01 = One Hundredth = 1/100
0.001 = One Thousandth = 1/1000
0.0001 = One Ten-Thousandth = 1/10000
0.00001 = One Hundred-Thousandth = 1/100000
Step 1: Count decimal places
Step 2: Write digits over appropriate power of 10
Step 3: Simplify by GCD
Step 4: Verify by division
0.1 ↔ 1/10
0.25 ↔ 1/4
0.5 ↔ 1/2
0.75 ↔ 3/4
0.125 ↔ 1/8
0.625 ↔ 5/8