Add 70/84 and 21/15
1st number: 70/84, 2nd number: 1 6/15
70/84 + 21/15 is 67/30.
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,
70/84 = 70 × 5/84 × 5 = 350/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Add the two like fractions:
350/420 + 588/420 = 350 + 588/420 = 938/420 - 938/420 simplified gives 67/30
- So, 70/84 + 21/15 = 67/30
In mixed form: 27/30
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