Add 72/60 and 28/21
1st number: 1 12/60, 2nd number: 1 7/21
72/60 + 28/21 is 38/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
72/60 = 72 × 7/60 × 7 = 504/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420 - Add the two like fractions:
504/420 + 560/420 = 504 + 560/420 = 1064/420 - 1064/420 simplified gives 38/15
- So, 72/60 + 28/21 = 38/15
In mixed form: 28/15
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