Add 45/70 and 21/12
1st number: 45/70, 2nd number: 1 9/12
45/70 + 21/12 is 67/28.
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,
45/70 = 45 × 6/70 × 6 = 270/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Add the two like fractions:
270/420 + 735/420 = 270 + 735/420 = 1005/420 - 1005/420 simplified gives 67/28
- So, 45/70 + 21/12 = 67/28
In mixed form: 211/28
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