Add 81/21 and 42/35
1st number: 3 18/21, 2nd number: 1 7/35
81/21 + 42/35 is 177/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
42/35 = 42 × 3/35 × 3 = 126/105 - Add the two like fractions:
405/105 + 126/105 = 405 + 126/105 = 531/105 - 531/105 simplified gives 177/35
- So, 81/21 + 42/35 = 177/35
In mixed form: 52/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/21+84/35 81/42+42/35 81/21+42/70 81/63+42/35