Add 21/12 and 42/70
1st number: 1 9/12, 2nd number: 42/70
21/12 + 42/70 is 47/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
42/70 = 42 × 6/70 × 6 = 252/420 - Add the two like fractions:
735/420 + 252/420 = 735 + 252/420 = 987/420 - 987/420 simplified gives 47/20
- So, 21/12 + 42/70 = 47/20
In mixed form: 27/20
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