Add 30/21 and 45/90
1st number: 1 9/21, 2nd number: 45/90
30/21 + 45/90 is 27/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
30/21 = 30 × 30/21 × 30 = 900/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
45/90 = 45 × 7/90 × 7 = 315/630 - Add the two like fractions:
900/630 + 315/630 = 900 + 315/630 = 1215/630 - 1215/630 simplified gives 27/14
- So, 30/21 + 45/90 = 27/14
In mixed form: 113/14
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