Add 81/60 and 72/21
1st number: 1 21/60, 2nd number: 3 9/21
81/60 + 72/21 is 669/140.
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,
81/60 = 81 × 7/60 × 7 = 567/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
72/21 = 72 × 20/21 × 20 = 1440/420 - Add the two like fractions:
567/420 + 1440/420 = 567 + 1440/420 = 2007/420 - 2007/420 simplified gives 669/140
- So, 81/60 + 72/21 = 669/140
In mixed form: 4109/140
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