Add 12/21 and 45/72
12/21 + 45/72 is 67/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
12/21 = 12 × 24/21 × 24 = 288/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Add the two like fractions:
288/504 + 315/504 = 288 + 315/504 = 603/504 - 603/504 simplified gives 67/56
- So, 12/21 + 45/72 = 67/56
In mixed form: 111/56
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