Add 20/21 and 36/40
20/21 + 36/40 is 389/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
20/21 = 20 × 40/21 × 40 = 800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
36/40 = 36 × 21/40 × 21 = 756/840 - Add the two like fractions:
800/840 + 756/840 = 800 + 756/840 = 1556/840 - 1556/840 simplified gives 389/210
- So, 20/21 + 36/40 = 389/210
In mixed form: 1179/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+36/40 20/21+72/40 20/42+36/40 20/21+36/80 60/21+36/40 20/63+36/40