Add 3/28 and 20/21
3/28 + 20/21 is 89/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
3/28 = 3 × 3/28 × 3 = 9/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Add the two like fractions:
9/84 + 80/84 = 9 + 80/84 = 89/84 - So, 3/28 + 20/21 = 89/84
In mixed form: 15/84
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