Add 40/84 and 28/21
1st number: 40/84, 2nd number: 1 7/21
40/84 + 28/21 is 38/21.
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,
40/84 = 40 × 1/84 × 1 = 40/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Add the two like fractions:
40/84 + 112/84 = 40 + 112/84 = 152/84 - 152/84 simplified gives 38/21
- So, 40/84 + 28/21 = 38/21
In mixed form: 117/21
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