Add 7/90 and 54/21
1st number: 7/90, 2nd number: 2 12/21
7/90 + 54/21 is 1669/630.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
7/90 = 7 × 7/90 × 7 = 49/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
54/21 = 54 × 30/21 × 30 = 1620/630 - Add the two like fractions:
49/630 + 1620/630 = 49 + 1620/630 = 1669/630 - So, 7/90 + 54/21 = 1669/630
In mixed form: 2409/630
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/90+54/21 7/90+54/42 21/90+54/21 7/90+54/63 35/90+54/21 49/90+54/21