Add 90/20 and 30/21
1st number: 4 10/20, 2nd number: 1 9/21
90/20 + 30/21 is 83/14.
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,
30/21 = 30 × 20/21 × 20 = 600/420 - Add the two like fractions:
1890/420 + 600/420 = 1890 + 600/420 = 2490/420 - 2490/420 simplified gives 83/14
- So, 90/20 + 30/21 = 83/14
In mixed form: 513/14
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