Add 21/90 and 21/84
21/90 + 21/84 is 29/60.
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,
21/90 = 21 × 14/90 × 14 = 294/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Add the two like fractions:
294/1260 + 315/1260 = 294 + 315/1260 = 609/1260 - 609/1260 simplified gives 29/60
- So, 21/90 + 21/84 = 29/60
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