Add 21/84 and 90/18
1st number: 21/84, 2nd number: 5 0/18
21/84 + 90/18 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
90/18 = 90 × 14/18 × 14 = 1260/252 - Add the two like fractions:
63/252 + 1260/252 = 63 + 1260/252 = 1323/252 - 1323/252 simplified gives 21/4
- So, 21/84 + 90/18 = 21/4
In mixed form: 51/4
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