Add 75/84 and 12/90
75/84 + 12/90 is 431/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
75/84 = 75 × 15/84 × 15 = 1125/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
12/90 = 12 × 14/90 × 14 = 168/1260 - Add the two like fractions:
1125/1260 + 168/1260 = 1125 + 168/1260 = 1293/1260 - 1293/1260 simplified gives 431/420
- So, 75/84 + 12/90 = 431/420
In mixed form: 111/420
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