Add 54/21 and 90/70
1st number: 2 12/21, 2nd number: 1 20/70
54/21 + 90/70 is 27/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
54/21 = 54 × 10/21 × 10 = 540/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Add the two like fractions:
540/210 + 270/210 = 540 + 270/210 = 810/210 - 810/210 simplified gives 27/7
- So, 54/21 + 90/70 = 27/7
In mixed form: 36/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/42+90/70 54/63+90/70