Add 21/12 and 81/70
1st number: 1 9/12, 2nd number: 1 11/70
21/12 + 81/70 is 407/140.
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,
81/70 = 81 × 6/70 × 6 = 486/420 - Add the two like fractions:
735/420 + 486/420 = 735 + 486/420 = 1221/420 - 1221/420 simplified gives 407/140
- So, 21/12 + 81/70 = 407/140
In mixed form: 2127/140
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