Add 84/42 and 30/20
1st number: 2 0/42, 2nd number: 1 10/20
84/42 + 30/20 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
84/42 = 84 × 10/42 × 10 = 840/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
30/20 = 30 × 21/20 × 21 = 630/420 - Add the two like fractions:
840/420 + 630/420 = 840 + 630/420 = 1470/420 - 1470/420 simplified gives 7/2
- So, 84/42 + 30/20 = 7/2
In mixed form: 31/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/42+60/20 84/42+30/40 84/42+90/20 84/42+30/60