Add 81/60 and 90/28
1st number: 1 21/60, 2nd number: 3 6/28
81/60 + 90/28 is 639/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 28 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 28 × 15 = 420,
90/28 = 90 × 15/28 × 15 = 1350/420 - Add the two like fractions:
567/420 + 1350/420 = 567 + 1350/420 = 1917/420 - 1917/420 simplified gives 639/140
- So, 81/60 + 90/28 = 639/140
In mixed form: 479/140
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