Add 18/42 and 1/21
18/42 + 1/21 is 10/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
1/21 = 1 × 2/21 × 2 = 2/42 - Add the two like fractions:
18/42 + 2/42 = 18 + 2/42 = 20/42 - 20/42 simplified gives 10/21
- So, 18/42 + 1/21 = 10/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/42+1/21 18/42+2/21 18/84+1/21 18/42+1/42 54/42+1/21 18/42+3/21 18/42+1/63 90/42+1/21 18/42+5/21 18/42+7/21