Add 18/42 and 21/63
18/42 + 21/63 is 16/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
18/42 = 18 × 3/42 × 3 = 54/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
21/63 = 21 × 2/63 × 2 = 42/126 - Add the two like fractions:
54/126 + 42/126 = 54 + 42/126 = 96/126 - 96/126 simplified gives 16/21
- So, 18/42 + 21/63 = 16/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/42+21/63 18/42+42/63 18/84+21/63 54/42+21/63 90/42+21/63