Add 30/21 and 90/9
1st number: 1 9/21, 2nd number: 10 0/9
30/21 + 90/9 is 80/7.
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,
90/9 = 90 × 7/9 × 7 = 630/63 - Add the two like fractions:
90/63 + 630/63 = 90 + 630/63 = 720/63 - 720/63 simplified gives 80/7
- So, 30/21 + 90/9 = 80/7
In mixed form: 113/7
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