Add 21/84 and 18/70
21/84 + 18/70 is 71/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 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 70 × 6 = 420,
18/70 = 18 × 6/70 × 6 = 108/420 - Add the two like fractions:
105/420 + 108/420 = 105 + 108/420 = 213/420 - 213/420 simplified gives 71/140
- So, 21/84 + 18/70 = 71/140
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