# What is 12/7+9/21?

How much is 127 plus 921. Step by step solution expressed as a proper or improper fraction, mixed number and decimal form.

• 157
• 2 17
• 2.1429 (rounded to 4 decimals)

## Step by step solution

127 + 921 = 4521

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

Multiples of 7 are   7, 14, 21 ....etc

Multiples of 21 are   21 ...etc

The LCM of 7 and 21 is 21. So, the common denominator of 127 and 921 is 21. Now change the fractions into equivalent fractions with common denominator

• 127 + 921
• 12 * 37 * 3 + 9 * 121 * 1
• 3621 + 921

• 3621 + 921
• 36 + 921
• 4521

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

Simplify

• 4521
• 157
• 2 17
1. ### Reduce fraction to its lowest terms

• 4521
• 45 ÷ 321 ÷ 3
• 157

The greatest common divisor of 45 and 21 is 3, the fraction 4521 can be simplified or reduced to lowest terms by dividing the numerator and denominator by 3.

2. ### Convert improper fraction 157 to mixed number

• 157
• 2 17

15 divided by 7 is 2 with a remainder of 1