Add 7/30 and 81/21
1st number: 7/30, 2nd number: 3 18/21
7/30 + 81/21 is 859/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
7/30 = 7 × 7/30 × 7 = 49/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Add the two like fractions:
49/210 + 810/210 = 49 + 810/210 = 859/210 - So, 7/30 + 81/21 = 859/210
In mixed form: 419/210
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