Add 30/21 and 20/72
1st number: 1 9/21, 2nd number: 20/72
30/21 + 20/72 is 215/126.
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,
30/21 = 30 × 24/21 × 24 = 720/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Add the two like fractions:
720/504 + 140/504 = 720 + 140/504 = 860/504 - 860/504 simplified gives 215/126
- So, 30/21 + 20/72 = 215/126
In mixed form: 189/126
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