Add 20/12 and 15/42
1st number: 1 8/12, 2nd number: 15/42
20/12 + 15/42 is 85/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
15/42 = 15 × 2/42 × 2 = 30/84 - Add the two like fractions:
140/84 + 30/84 = 140 + 30/84 = 170/84 - 170/84 simplified gives 85/42
- So, 20/12 + 15/42 = 85/42
In mixed form: 21/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/12+15/42 20/12+30/42 20/24+15/42 20/12+15/84 60/12+15/42 20/12+45/42 20/36+15/42 20/12+75/42 20/60+15/42 20/84+15/42