What is 3/9 plus 7/8? (Answer: 29/24)

Exact Answer

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Problem: What is 3/9 plus 7/8?
Formula / Expression: 3/9 + 7/8
Final Answer: 1 5/24 (29/24)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 9 and 8 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 9 × 8 = 72.
Working: LCD(9, 8) = 72

Step 2: Convert to Equivalent Fractions with Common Denominator 72
Multiply the numerator and denominator of 3/9 by 8, and multiply the numerator and denominator of 7/8 by 9 so both fractions share the common base 72.
Working: 3 × 8/9 × 8 = 24/72 and 7 × 9/8 × 9 = 63/72

Step 3: Add the Numerators
Now add the numerators (24 + 63 = 87) and keep the common denominator 72 unchanged.
Working: 24 + 63/72 = 87/72

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 87 and 72, which is 3. Divide both the numerator and denominator by 3.
Working: 87 ÷ 3/72 ÷ 3 = 29/24

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (29) is greater than the denominator (24), divide 29 by 24: it goes in 1 whole time(s) with a remainder of 5, giving the mixed number 1 5/24.
Working: 29/24 = 1 5/24

Step 6: Decimal & Percentage Representation
Dividing the numerator 29 by denominator 24 produces a repeating decimal (approximately 1.208333, or 120.8333%).
Working: 29 ÷ 24 = 1.208333 (120.8333%)

Key Values:
- Simplified Fraction: 29/24
- Mixed Number Form: 1 5/24
- Decimal Value: 1.208333
- Percentage: 120.8333%

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Solved with FractionsCalc:
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3/9 + 7/8 = 29/24

Simplified Fraction

29/24

Mixed Number

1 5/24

Decimal Value

1.208333

Percentage

120.8333%

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Step-by-Step Solution: 3/9 + 7/8

Step 1

Find the Least Common Denominator (LCD)

The denominators 9 and 8 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 9 × 8 = 72.

LCD(9, 8) = 72

Step 2

Convert to Equivalent Fractions with Common Denominator 72

Multiply the numerator and denominator of 3/9 by 8, and multiply the numerator and denominator of 7/8 by 9 so both fractions share the common base 72.

3 × 8/9 × 8 = 24/72 and 7 × 9/8 × 9 = 63/72

Step 3

Add the Numerators

Now add the numerators (24 + 63 = 87) and keep the common denominator 72 unchanged.

24 + 63/72 = 87/72

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 87 and 72, which is 3. Divide both the numerator and denominator by 3.

87 ÷ 3/72 ÷ 3 = 29/24

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (29) is greater than the denominator (24), divide 29 by 24: it goes in 1 whole time(s) with a remainder of 5, giving the mixed number 1 5/24.

29/24 = 15/24

Step 6

Decimal & Percentage Representation

Dividing the numerator 29 by denominator 24 produces a repeating decimal (approximately 1.208333, or 120.8333%).

29 ÷ 24 = 1.208333 (120.8333%)

Visual Representation

The diagram below illustrates 3/9 plus 7/8 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`29/24`
Mixed Number Form	`1 5/24`
Decimal Form	`1.208333`
Percentage	`120.8333%`

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Frequently Asked Questions

What is 3/9 plus 7/8 as a fraction?

3/9 + 7/8 in simplest fraction form is 29/24 (or 1 5/24 as a mixed number).

What is 3/9 plus 7/8 as a decimal?

3/9 + 7/8 converted to a decimal is 1.208333.

What is 3/9 plus 7/8 as a percentage?

3/9 + 7/8 expressed as a percentage is 120.8333%.

How do you write 3/9 plus 7/8 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 29/24 can be written as the mixed number 1 5/24.

Does 3/9 plus 7/8 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.208333...) because the denominator contains prime factors other than 2 and 5.