Add 84/72 and 28/21
1st number: 1 12/72, 2nd number: 1 7/21
84/72 + 28/21 is 5/2.
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,
84/72 = 84 × 7/72 × 7 = 588/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
28/21 = 28 × 24/21 × 24 = 672/504 - Add the two like fractions:
588/504 + 672/504 = 588 + 672/504 = 1260/504 - 1260/504 simplified gives 5/2
- So, 84/72 + 28/21 = 5/2
In mixed form: 21/2
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