Add 20/21 and 9/45
20/21 + 9/45 is 121/105.
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,
20/21 = 20 × 15/21 × 15 = 300/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
9/45 = 9 × 7/45 × 7 = 63/315 - Add the two like fractions:
300/315 + 63/315 = 300 + 63/315 = 363/315 - 363/315 simplified gives 121/105
- So, 20/21 + 9/45 = 121/105
In mixed form: 116/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+9/45 20/21+18/45 20/42+9/45 20/21+9/90 60/21+9/45 20/21+27/45 20/63+9/45 20/21+63/45