Add 90/28 and 12/72
1st number: 3 6/28, 2nd number: 12/72
90/28 + 12/72 is 71/21.
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,
90/28 = 90 × 18/28 × 18 = 1620/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504 - Add the two like fractions:
1620/504 + 84/504 = 1620 + 84/504 = 1704/504 - 1704/504 simplified gives 71/21
- So, 90/28 + 12/72 = 71/21
In mixed form: 38/21
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