Add 42/84 and 45/72
42/84 + 45/72 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
42/84 = 42 × 6/84 × 6 = 252/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Add the two like fractions:
252/504 + 315/504 = 252 + 315/504 = 567/504 - 567/504 simplified gives 9/8
- So, 42/84 + 45/72 = 9/8
In mixed form: 11/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84+90/72