Add 21/42 and 8/54
21/42 + 8/54 is 35/54.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
8/54 = 8 × 7/54 × 7 = 56/378 - Add the two like fractions:
189/378 + 56/378 = 189 + 56/378 = 245/378 - 245/378 simplified gives 35/54
- So, 21/42 + 8/54 = 35/54
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42+16/54 21/84+8/54 63/42+8/54 21/42+24/54 21/42+40/54 21/42+56/54