Add 5/84 and 81/90
5/84 + 81/90 is 403/420.
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,
5/84 = 5 × 15/84 × 15 = 75/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
81/90 = 81 × 14/90 × 14 = 1134/1260 - Add the two like fractions:
75/1260 + 1134/1260 = 75 + 1134/1260 = 1209/1260 - 1209/1260 simplified gives 403/420
- So, 5/84 + 81/90 = 403/420
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