Add 30/40 and 70/81
30/40 + 70/81 is 523/324.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 40 × 81 = 3240,
30/40 = 30 × 81/40 × 81 = 2430/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
70/81 = 70 × 40/81 × 40 = 2800/3240 - Add the two like fractions:
2430/3240 + 2800/3240 = 2430 + 2800/3240 = 5230/3240 - 5230/3240 simplified gives 523/324
- So, 30/40 + 70/81 = 523/324
In mixed form: 1199/324
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/40+70/81 30/80+70/81 90/40+70/81