Add 84/21 and 72/45
1st number: 4 0/21, 2nd number: 1 27/45
84/21 + 72/45 is 28/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
84/21 = 84 × 15/21 × 15 = 1260/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
72/45 = 72 × 7/45 × 7 = 504/315 - Add the two like fractions:
1260/315 + 504/315 = 1260 + 504/315 = 1764/315 - 1764/315 simplified gives 28/5
- So, 84/21 + 72/45 = 28/5
In mixed form: 53/5
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