Add 72/21 and 75/42
1st number: 3 9/21, 2nd number: 1 33/42
72/21 + 75/42 is 73/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
75/42 = 75 × 1/42 × 1 = 75/42 - Add the two like fractions:
144/42 + 75/42 = 144 + 75/42 = 219/42 - 219/42 simplified gives 73/14
- So, 72/21 + 75/42 = 73/14
In mixed form: 53/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/42+75/42 72/21+75/84 72/63+75/42