Add 28/2 and 90/21
1st number: 14 0/2, 2nd number: 4 6/21
28/2 + 90/21 is 128/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
28/2 = 28 × 21/2 × 21 = 588/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
90/21 = 90 × 2/21 × 2 = 180/42 - Add the two like fractions:
588/42 + 180/42 = 588 + 180/42 = 768/42 - 768/42 simplified gives 128/7
- So, 28/2 + 90/21 = 128/7
In mixed form: 182/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/2+90/21 28/4+90/21 28/2+90/42 84/2+90/21 28/6+90/21 28/2+90/63 28/10+90/21 28/14+90/21