Add 21/70 and 3/12
21/70 + 3/12 is 11/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 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 12 × 35 = 420,
3/12 = 3 × 35/12 × 35 = 105/420 - Add the two like fractions:
126/420 + 105/420 = 126 + 105/420 = 231/420 - 231/420 simplified gives 11/20
- So, 21/70 + 3/12 = 11/20
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