Add 28/84 and 90/72
1st number: 28/84, 2nd number: 1 18/72
28/84 + 90/72 is 19/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
28/84 = 28 × 6/84 × 6 = 168/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Add the two like fractions:
168/504 + 630/504 = 168 + 630/504 = 798/504 - 798/504 simplified gives 19/12
- So, 28/84 + 90/72 = 19/12
In mixed form: 17/12
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