Add 21/70 and 15/84
21/70 + 15/84 is 67/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
15/84 = 15 × 5/84 × 5 = 75/420 - Add the two like fractions:
126/420 + 75/420 = 126 + 75/420 = 201/420 - 201/420 simplified gives 67/140
- So, 21/70 + 15/84 = 67/140
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