Add 72/9 and 4/21
1st number: 8 0/9, 2nd number: 4/21
72/9 + 4/21 is 172/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
72/9 = 72 × 7/9 × 7 = 504/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
4/21 = 4 × 3/21 × 3 = 12/63 - Add the two like fractions:
504/63 + 12/63 = 504 + 12/63 = 516/63 - 516/63 simplified gives 172/21
- So, 72/9 + 4/21 = 172/21
In mixed form: 84/21
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