Add 84/72 and 4/21
1st number: 1 12/72, 2nd number: 4/21
84/72 + 4/21 is 19/14.
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,
4/21 = 4 × 24/21 × 24 = 96/504 - Add the two like fractions:
588/504 + 96/504 = 588 + 96/504 = 684/504 - 684/504 simplified gives 19/14
- So, 84/72 + 4/21 = 19/14
In mixed form: 15/14
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