Add 72/9 and 45/21
1st number: 8 0/9, 2nd number: 2 3/21
72/9 + 45/21 is 71/7.
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,
45/21 = 45 × 3/21 × 3 = 135/63 - Add the two like fractions:
504/63 + 135/63 = 504 + 135/63 = 639/63 - 639/63 simplified gives 71/7
- So, 72/9 + 45/21 = 71/7
In mixed form: 101/7
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