Add 21/84 and 40/45
21/84 + 40/45 is 41/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
40/45 = 40 × 28/45 × 28 = 1120/1260 - Add the two like fractions:
315/1260 + 1120/1260 = 315 + 1120/1260 = 1435/1260 - 1435/1260 simplified gives 41/36
- So, 21/84 + 40/45 = 41/36
In mixed form: 15/36
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84+40/45 21/84+80/45 21/84+40/90 63/84+40/45