Add 21/84 and 40/15
1st number: 21/84, 2nd number: 2 10/15
21/84 + 40/15 is 35/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
40/15 = 40 × 28/15 × 28 = 1120/420 - Add the two like fractions:
105/420 + 1120/420 = 105 + 1120/420 = 1225/420 - 1225/420 simplified gives 35/12
- So, 21/84 + 40/15 = 35/12
In mixed form: 211/12
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