Add 21/84 and 90/20
1st number: 21/84, 2nd number: 4 10/20
21/84 + 90/20 is 19/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420 - Add the two like fractions:
105/420 + 1890/420 = 105 + 1890/420 = 1995/420 - 1995/420 simplified gives 19/4
- So, 21/84 + 90/20 = 19/4
In mixed form: 43/4
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