Add 21/40 and 84/98
21/40 + 84/98 is 387/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 98 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 40 × 49 = 1960,
21/40 = 21 × 49/40 × 49 = 1029/1960 - Likewise, for the 2nd fraction, since 98 × 20 = 1960,
84/98 = 84 × 20/98 × 20 = 1680/1960 - Add the two like fractions:
1029/1960 + 1680/1960 = 1029 + 1680/1960 = 2709/1960 - 2709/1960 simplified gives 387/280
- So, 21/40 + 84/98 = 387/280
In mixed form: 1107/280
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/40+84/98 21/80+84/98 63/40+84/98