Add 3/21 and 18/9
1st number: 3/21, 2nd number: 2 0/9
3/21 + 18/9 is 15/7.
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,
3/21 = 3 × 3/21 × 3 = 9/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
18/9 = 18 × 7/9 × 7 = 126/63 - Add the two like fractions:
9/63 + 126/63 = 9 + 126/63 = 135/63 - 135/63 simplified gives 15/7
- So, 3/21 + 18/9 = 15/7
In mixed form: 21/7
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