Add 20/42 and 30/40
20/42 + 30/40 is 103/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
20/42 = 20 × 20/42 × 20 = 400/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Add the two like fractions:
400/840 + 630/840 = 400 + 630/840 = 1030/840 - 1030/840 simplified gives 103/84
- So, 20/42 + 30/40 = 103/84
In mixed form: 119/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/42+30/40 20/42+60/40 20/84+30/40 20/42+30/80 60/42+30/40 20/42+90/40