Add 20/21 and 30/28
1st number: 20/21, 2nd number: 1 2/28
20/21 + 30/28 is 85/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
30/28 = 30 × 3/28 × 3 = 90/84 - Add the two like fractions:
80/84 + 90/84 = 80 + 90/84 = 170/84 - 170/84 simplified gives 85/42
- So, 20/21 + 30/28 = 85/42
In mixed form: 21/42
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