Add 90/28 and 81/42
1st number: 3 6/28, 2nd number: 1 39/42
90/28 + 81/42 is 36/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84 - Add the two like fractions:
270/84 + 162/84 = 270 + 162/84 = 432/84 - 432/84 simplified gives 36/7
- So, 90/28 + 81/42 = 36/7
In mixed form: 51/7
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