Add 90/28 and 81/60
1st number: 3 6/28, 2nd number: 1 21/60
90/28 + 81/60 is 639/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
90/28 = 90 × 15/28 × 15 = 1350/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
81/60 = 81 × 7/60 × 7 = 567/420 - Add the two like fractions:
1350/420 + 567/420 = 1350 + 567/420 = 1917/420 - 1917/420 simplified gives 639/140
- So, 90/28 + 81/60 = 639/140
In mixed form: 479/140
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