Add 27/40 and 2/21
27/40 + 2/21 is 647/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
27/40 = 27 × 21/40 × 21 = 567/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
2/21 = 2 × 40/21 × 40 = 80/840 - Add the two like fractions:
567/840 + 80/840 = 567 + 80/840 = 647/840 - So, 27/40 + 2/21 = 647/840
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/40+2/21 27/40+4/21 27/80+2/21 27/40+2/42 81/40+2/21 27/40+6/21 27/40+2/63 27/40+10/21 27/40+14/21