Add 18/45 and 5/21
18/45 + 5/21 is 67/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
18/45 = 18 × 7/45 × 7 = 126/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
5/21 = 5 × 15/21 × 15 = 75/315 - Add the two like fractions:
126/315 + 75/315 = 126 + 75/315 = 201/315 - 201/315 simplified gives 67/105
- So, 18/45 + 5/21 = 67/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/45+5/21 18/45+10/21 18/90+5/21 18/45+5/42 54/45+5/21 18/45+15/21 18/45+5/63 90/45+5/21 18/45+25/21 18/45+35/21