Add 90/20 and 20/21
1st number: 4 10/20, 2nd number: 20/21
90/20 + 20/21 is 229/42.
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,
20/21 = 20 × 20/21 × 20 = 400/420 - Add the two like fractions:
1890/420 + 400/420 = 1890 + 400/420 = 2290/420 - 2290/420 simplified gives 229/42
- So, 90/20 + 20/21 = 229/42
In mixed form: 519/42
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