Add 20/84 and 40/21
1st number: 20/84, 2nd number: 1 19/21
20/84 + 40/21 is 15/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
20/84 = 20 × 1/84 × 1 = 20/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
40/21 = 40 × 4/21 × 4 = 160/84 - Add the two like fractions:
20/84 + 160/84 = 20 + 160/84 = 180/84 - 180/84 simplified gives 15/7
- So, 20/84 + 40/21 = 15/7
In mixed form: 21/7
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