Add 28/21 and 48/40
1st number: 1 7/21, 2nd number: 1 8/40
28/21 + 48/40 is 38/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
28/21 = 28 × 40/21 × 40 = 1120/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
48/40 = 48 × 21/40 × 21 = 1008/840 - Add the two like fractions:
1120/840 + 1008/840 = 1120 + 1008/840 = 2128/840 - 2128/840 simplified gives 38/15
- So, 28/21 + 48/40 = 38/15
In mixed form: 28/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/21+48/40 28/21+96/40 28/42+48/40 28/21+48/80 84/21+48/40 28/63+48/40