Add 84/20 and 7/21
1st number: 4 4/20, 2nd number: 7/21
84/20 + 7/21 is 68/15.
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,
84/20 = 84 × 21/20 × 21 = 1764/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
7/21 = 7 × 20/21 × 20 = 140/420 - Add the two like fractions:
1764/420 + 140/420 = 1764 + 140/420 = 1904/420 - 1904/420 simplified gives 68/15
- So, 84/20 + 7/21 = 68/15
In mixed form: 48/15
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