Add 72/21 and 70/63
1st number: 3 9/21, 2nd number: 1 7/63
72/21 + 70/63 is 286/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
70/63 = 70 × 1/63 × 1 = 70/63 - Add the two like fractions:
216/63 + 70/63 = 216 + 70/63 = 286/63 - So, 72/21 + 70/63 = 286/63
In mixed form: 434/63
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