Add 21/12 and 20/70
1st number: 1 9/12, 2nd number: 20/70
21/12 + 20/70 is 57/28.
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,
20/70 = 20 × 6/70 × 6 = 120/420 - Add the two like fractions:
735/420 + 120/420 = 735 + 120/420 = 855/420 - 855/420 simplified gives 57/28
- So, 21/12 + 20/70 = 57/28
In mixed form: 21/28
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