Add 72/20 and 28/21
1st number: 3 12/20, 2nd number: 1 7/21
72/20 + 28/21 is 74/15.
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,
28/21 = 28 × 20/21 × 20 = 560/420 - Add the two like fractions:
1512/420 + 560/420 = 1512 + 560/420 = 2072/420 - 2072/420 simplified gives 74/15
- So, 72/20 + 28/21 = 74/15
In mixed form: 414/15
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