Add 10/42 and 20/30
10/42 + 20/30 is 19/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
10/42 = 10 × 5/42 × 5 = 50/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Add the two like fractions:
50/210 + 140/210 = 50 + 140/210 = 190/210 - 190/210 simplified gives 19/21
- So, 10/42 + 20/30 = 19/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/42+20/30 10/42+40/30 10/84+20/30 10/42+20/60 30/42+20/30 10/42+60/30 10/42+20/90 50/42+20/30 70/42+20/30