Add 90/42 and 21/70
1st number: 2 6/42, 2nd number: 21/70
90/42 + 21/70 is 171/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
90/42 = 90 × 5/42 × 5 = 450/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Add the two like fractions:
450/210 + 63/210 = 450 + 63/210 = 513/210 - 513/210 simplified gives 171/70
- So, 90/42 + 21/70 = 171/70
In mixed form: 231/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/42+42/70 90/84+21/70 90/42+63/70