Add 12/90 and 81/84
12/90 + 81/84 is 461/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
12/90 = 12 × 14/90 × 14 = 168/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
81/84 = 81 × 15/84 × 15 = 1215/1260 - Add the two like fractions:
168/1260 + 1215/1260 = 168 + 1215/1260 = 1383/1260 - 1383/1260 simplified gives 461/420
- So, 12/90 + 81/84 = 461/420
In mixed form: 141/420
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