Add 81/28 and 12/90
1st number: 2 25/28, 2nd number: 12/90
81/28 + 12/90 is 1271/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
81/28 = 81 × 45/28 × 45 = 3645/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
12/90 = 12 × 14/90 × 14 = 168/1260 - Add the two like fractions:
3645/1260 + 168/1260 = 3645 + 168/1260 = 3813/1260 - 3813/1260 simplified gives 1271/420
- So, 81/28 + 12/90 = 1271/420
In mixed form: 311/420
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