Add 20/72 and 64/21
1st number: 20/72, 2nd number: 3 1/21
20/72 + 64/21 is 419/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
64/21 = 64 × 24/21 × 24 = 1536/504 - Add the two like fractions:
140/504 + 1536/504 = 140 + 1536/504 = 1676/504 - 1676/504 simplified gives 419/126
- So, 20/72 + 64/21 = 419/126
In mixed form: 341/126
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