Add 21/30 and 70/84
21/30 + 70/84 is 23/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
70/84 = 70 × 5/84 × 5 = 350/420 - Add the two like fractions:
294/420 + 350/420 = 294 + 350/420 = 644/420 - 644/420 simplified gives 23/15
- So, 21/30 + 70/84 = 23/15
In mixed form: 18/15
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