Add 3/21 and 18/45
3/21 + 18/45 is 19/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
3/21 = 3 × 15/21 × 15 = 45/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
18/45 = 18 × 7/45 × 7 = 126/315 - Add the two like fractions:
45/315 + 126/315 = 45 + 126/315 = 171/315 - 171/315 simplified gives 19/35
- So, 3/21 + 18/45 = 19/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/21+18/45 3/21+36/45 3/42+18/45 3/21+18/90 9/21+18/45 3/21+54/45 3/63+18/45 15/21+18/45 3/21+90/45