Add 40/20 and 21/42
1st number: 2 0/20, 2nd number: 21/42
40/20 + 21/42 is 5/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
40/20 = 40 × 21/20 × 21 = 840/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Add the two like fractions:
840/420 + 210/420 = 840 + 210/420 = 1050/420 - 1050/420 simplified gives 5/2
- So, 40/20 + 21/42 = 5/2
In mixed form: 21/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/20+21/42 40/20+21/84 40/20+63/42 40/60+21/42