Add 30/21 and 21/9
1st number: 1 9/21, 2nd number: 2 3/9
30/21 + 21/9 is 79/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
30/21 = 30 × 3/21 × 3 = 90/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63 - Add the two like fractions:
90/63 + 147/63 = 90 + 147/63 = 237/63 - 237/63 simplified gives 79/21
- So, 30/21 + 21/9 = 79/21
In mixed form: 316/21
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