# What is 20/15+9/21?

How much is 2015 plus 921. Step by step solution expressed as a proper or improper fraction, mixed number and decimal form.

• 3721
• 1 1621
• 1.7619 (rounded to 4 decimals)

## Step by step solution

2015 + 921 = 185105

1. ### Find common denominator by finding the Least Common Multiple(LCM)

Multiples of 15 are   15, 30, 45, 60, 75, 90, 105 ....etc

Multiples of 21 are   21, 42, 63, 84, 105 ...etc

The LCM of 15 and 21 is 105. So, the common denominator of 2015 and 921 is 105. Now change the fractions into equivalent fractions with common denominator

• 2015 + 921
• 20 * 715 * 7 + 9 * 521 * 5
• 140105 + 45105

• 140105 + 45105
• 140 + 45105
• 185105

Add the numerators and place the sum over the common denominator.

Simplify

• 185105
• 3721
• 1 1621
1. ### Reduce fraction to its lowest terms

• 185105
• 185 ÷ 5105 ÷ 5
• 3721

The greatest common divisor of 185 and 105 is 5, the fraction 185105 can be simplified or reduced to lowest terms by dividing the numerator and denominator by 5.

2. ### Convert improper fraction 3721 to mixed number

• 3721
• 1 1621

37 divided by 21 is 1 with a remainder of 16