Add 15/42 and 81/90
15/42 + 81/90 is 44/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
15/42 = 15 × 15/42 × 15 = 225/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Add the two like fractions:
225/630 + 567/630 = 225 + 567/630 = 792/630 - 792/630 simplified gives 44/35
- So, 15/42 + 81/90 = 44/35
In mixed form: 19/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/42+81/90 15/84+81/90 45/42+81/90 75/42+81/90