Add 15/30 and 70/81
15/30 + 70/81 is 221/162.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
15/30 = 15 × 27/30 × 27 = 405/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
70/81 = 70 × 10/81 × 10 = 700/810 - Add the two like fractions:
405/810 + 700/810 = 405 + 700/810 = 1105/810 - 1105/810 simplified gives 221/162
- So, 15/30 + 70/81 = 221/162
In mixed form: 159/162
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 15/60+70/81 45/30+70/81 15/90+70/81 75/30+70/81