Add 21/28 and 20/72
21/28 + 20/72 is 37/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 28 × 18 = 504,
21/28 = 21 × 18/28 × 18 = 378/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Add the two like fractions:
378/504 + 140/504 = 378 + 140/504 = 518/504 - 518/504 simplified gives 37/36
- So, 21/28 + 20/72 = 37/36
In mixed form: 11/36
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