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