Add 21/84 and 42/70
21/84 + 42/70 is 17/20.
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,
42/70 = 42 × 6/70 × 6 = 252/420 - Add the two like fractions:
105/420 + 252/420 = 105 + 252/420 = 357/420 - 357/420 simplified gives 17/20
- So, 21/84 + 42/70 = 17/20
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