Add 3/21 and 20/35
3/21 + 20/35 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
3/21 = 3 × 5/21 × 5 = 15/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
20/35 = 20 × 3/35 × 3 = 60/105 - Add the two like fractions:
15/105 + 60/105 = 15 + 60/105 = 75/105 - 75/105 simplified gives 5/7
- So, 3/21 + 20/35 = 5/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/21+20/35 3/21+40/35 3/42+20/35 3/21+20/70 9/21+20/35 3/21+60/35 3/63+20/35 15/21+20/35