Add 36/40 and 30/21
1st number: 36/40, 2nd number: 1 9/21
36/40 + 30/21 is 163/70.
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,
36/40 = 36 × 21/40 × 21 = 756/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
30/21 = 30 × 40/21 × 40 = 1200/840 - Add the two like fractions:
756/840 + 1200/840 = 756 + 1200/840 = 1956/840 - 1956/840 simplified gives 163/70
- So, 36/40 + 30/21 = 163/70
In mixed form: 223/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/40+30/21 36/40+60/21 36/80+30/21 36/40+30/42 36/40+90/21 36/40+30/63