What is 10/36 plus 15/21? (Answer: 125/126)

Exact Answer

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Problem: What is 10/36 plus 15/21?
Formula / Expression: 10/36 + 15/21
Final Answer: 125/126
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 36 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 252 (which is smaller than their product 36 × 21 = 756, keeping the calculation simpler).
Working: LCD(36, 21) = 252

Step 2: Convert to Equivalent Fractions with Common Denominator 252
Multiply the numerator and denominator of 10/36 by 7, and multiply the numerator and denominator of 15/21 by 12 so both fractions share the common base 252.
Working: 10 × 7/36 × 7 = 70/252 and 15 × 12/21 × 12 = 180/252

Step 3: Add the Numerators
Now add the numerators (70 + 180 = 250) and keep the common denominator 252 unchanged.
Working: 70 + 180/252 = 250/252

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 250 and 252, which is 2. Divide both the numerator and denominator by 2.
Working: 250 ÷ 2/252 ÷ 2 = 125/126

Step 5: Decimal & Percentage Representation
Dividing the numerator 125 by denominator 126 produces a repeating decimal (approximately 0.992063, or 99.2063%).
Working: 125 ÷ 126 = 0.992063 (99.2063%)

Key Values:
- Simplified Fraction: 125/126
- Mixed Number Form: 125/126
- Decimal Value: 0.992063
- Percentage: 99.2063%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-10-36-plus-15-21/
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10/36 + 15/21 = 125/126

Simplified Fraction

125/126

Mixed Number

Proper (125/126)

Decimal Value

0.992063

Percentage

99.2063%

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Step-by-Step Solution: 10/36 + 15/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 36 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 252 (which is smaller than their product 36 × 21 = 756, keeping the calculation simpler).

LCD(36, 21) = 252

Step 2

Convert to Equivalent Fractions with Common Denominator 252

Multiply the numerator and denominator of 10/36 by 7, and multiply the numerator and denominator of 15/21 by 12 so both fractions share the common base 252.

10 × 7/36 × 7 = 70/252 and 15 × 12/21 × 12 = 180/252

Step 3

Add the Numerators

Now add the numerators (70 + 180 = 250) and keep the common denominator 252 unchanged.

70 + 180/252 = 250/252

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 250 and 252, which is 2. Divide both the numerator and denominator by 2.

250 ÷ 2/252 ÷ 2 = 125/126

Step 5

Decimal & Percentage Representation

Dividing the numerator 125 by denominator 126 produces a repeating decimal (approximately 0.992063, or 99.2063%).

125 ÷ 126 = 0.992063 (99.2063%)

Visual Representation

The diagram below illustrates 10/36 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`125/126`
Mixed Number Form	`125/126`
Decimal Form	`0.992063`
Percentage	`99.2063%`

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Frequently Asked Questions

What is 10/36 plus 15/21 as a fraction?

10/36 + 15/21 in simplest fraction form is 125/126.

What is 10/36 plus 15/21 as a decimal?

10/36 + 15/21 converted to a decimal is 0.992063.

What is 10/36 plus 15/21 as a percentage?

10/36 + 15/21 expressed as a percentage is 99.2063%.

Does 10/36 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.992063...) because the denominator contains prime factors other than 2 and 5.