Add 8/21 and 28/54
8/21 + 28/54 is 170/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
8/21 = 8 × 18/21 × 18 = 144/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
28/54 = 28 × 7/54 × 7 = 196/378 - Add the two like fractions:
144/378 + 196/378 = 144 + 196/378 = 340/378 - 340/378 simplified gives 170/189
- So, 8/21 + 28/54 = 170/189
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/21+28/54 8/21+56/54 8/42+28/54 24/21+28/54 8/21+84/54 8/63+28/54 40/21+28/54 56/21+28/54