Add 90/20 and 10/21
1st number: 4 10/20, 2nd number: 10/21
90/20 + 10/21 is 209/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 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 21 × 20 = 420,
10/21 = 10 × 20/21 × 20 = 200/420 - Add the two like fractions:
1890/420 + 200/420 = 1890 + 200/420 = 2090/420 - 2090/420 simplified gives 209/42
- So, 90/20 + 10/21 = 209/42
In mixed form: 441/42
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