Add 84/56 and 90/21
1st number: 1 28/56, 2nd number: 4 6/21
84/56 + 90/21 is 81/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
84/56 = 84 × 3/56 × 3 = 252/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168 - Add the two like fractions:
252/168 + 720/168 = 252 + 720/168 = 972/168 - 972/168 simplified gives 81/14
- So, 84/56 + 90/21 = 81/14
In mixed form: 511/14
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