Add 72/20 and 84/21
1st number: 3 12/20, 2nd number: 4 0/21
72/20 + 84/21 is 38/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
84/21 = 84 × 20/21 × 20 = 1680/420 - Add the two like fractions:
1512/420 + 1680/420 = 1512 + 1680/420 = 3192/420 - 3192/420 simplified gives 38/5
- So, 72/20 + 84/21 = 38/5
In mixed form: 73/5
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