Add 7/90 and 81/21
1st number: 7/90, 2nd number: 3 18/21
7/90 + 81/21 is 2479/630.
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,
81/21 = 81 × 30/21 × 30 = 2430/630 - Add the two like fractions:
49/630 + 2430/630 = 49 + 2430/630 = 2479/630 - So, 7/90 + 81/21 = 2479/630
In mixed form: 3589/630
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