Add 42/81 and 20/45
42/81 + 20/45 is 26/27.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
42/81 = 42 × 5/81 × 5 = 210/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
20/45 = 20 × 9/45 × 9 = 180/405 - Add the two like fractions:
210/405 + 180/405 = 210 + 180/405 = 390/405 - 390/405 simplified gives 26/27
- So, 42/81 + 20/45 = 26/27
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/81+20/45 42/81+40/45 42/81+20/90 42/81+60/45