Add 72/42 and 70/20
1st number: 1 30/42, 2nd number: 3 10/20
72/42 + 70/20 is 73/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
72/42 = 72 × 10/42 × 10 = 720/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420 - Add the two like fractions:
720/420 + 1470/420 = 720 + 1470/420 = 2190/420 - 2190/420 simplified gives 73/14
- So, 72/42 + 70/20 = 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: 72/84+70/20 72/42+70/40 72/42+70/60