What is 12/46 plus 15/21? (Answer: 157/161)

Exact Answer

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Problem: What is 12/46 plus 15/21?
Formula / Expression: 12/46 + 15/21
Final Answer: 157/161
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 46 and 21 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 46 × 21 = 966.
Working: LCD(46, 21) = 966

Step 2: Convert to Equivalent Fractions with Common Denominator 966
Multiply the numerator and denominator of 12/46 by 21, and multiply the numerator and denominator of 15/21 by 46 so both fractions share the common base 966.
Working: 12 × 21/46 × 21 = 252/966 and 15 × 46/21 × 46 = 690/966

Step 3: Add the Numerators
Now add the numerators (252 + 690 = 942) and keep the common denominator 966 unchanged.
Working: 252 + 690/966 = 942/966

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 942 and 966, which is 6. Divide both the numerator and denominator by 6.
Working: 942 ÷ 6/966 ÷ 6 = 157/161

Step 5: Decimal & Percentage Representation
Dividing the numerator 157 by denominator 161 produces a repeating decimal (approximately 0.975155, or 97.5155%).
Working: 157 ÷ 161 = 0.975155 (97.5155%)

Key Values:
- Simplified Fraction: 157/161
- Mixed Number Form: 157/161
- Decimal Value: 0.975155
- Percentage: 97.5155%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-12-46-plus-15-21/
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12/46 + 15/21 = 157/161

Simplified Fraction

157/161

Mixed Number

Proper (157/161)

Decimal Value

0.975155

Percentage

97.5155%

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Step-by-Step Solution: 12/46 + 15/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 46 and 21 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 46 × 21 = 966.

LCD(46, 21) = 966

Step 2

Convert to Equivalent Fractions with Common Denominator 966

Multiply the numerator and denominator of 12/46 by 21, and multiply the numerator and denominator of 15/21 by 46 so both fractions share the common base 966.

12 × 21/46 × 21 = 252/966 and 15 × 46/21 × 46 = 690/966

Step 3

Add the Numerators

Now add the numerators (252 + 690 = 942) and keep the common denominator 966 unchanged.

252 + 690/966 = 942/966

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 942 and 966, which is 6. Divide both the numerator and denominator by 6.

942 ÷ 6/966 ÷ 6 = 157/161

Step 5

Decimal & Percentage Representation

Dividing the numerator 157 by denominator 161 produces a repeating decimal (approximately 0.975155, or 97.5155%).

157 ÷ 161 = 0.975155 (97.5155%)

Visual Representation

The diagram below illustrates 12/46 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`157/161`
Mixed Number Form	`157/161`
Decimal Form	`0.975155`
Percentage	`97.5155%`

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Frequently Asked Questions

What is 12/46 plus 15/21 as a fraction?

12/46 + 15/21 in simplest fraction form is 157/161.

What is 12/46 plus 15/21 as a decimal?

12/46 + 15/21 converted to a decimal is 0.975155.

What is 12/46 plus 15/21 as a percentage?

12/46 + 15/21 expressed as a percentage is 97.5155%.

Does 12/46 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.975155...) because the denominator contains prime factors other than 2 and 5.