Add 7/40 and 1/21
7/40 + 1/21 is 187/840.
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,
7/40 = 7 × 21/40 × 21 = 147/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
1/21 = 1 × 40/21 × 40 = 40/840 - Add the two like fractions:
147/840 + 40/840 = 147 + 40/840 = 187/840 - So, 7/40 + 1/21 = 187/840
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/40+1/21 7/40+2/21 7/80+1/21 7/40+1/42 21/40+1/21 7/40+3/21 7/40+1/63 35/40+1/21 7/40+5/21 49/40+1/21 7/40+7/21