Add 84/36 and 90/21
1st number: 2 12/36, 2nd number: 4 6/21
84/36 + 90/21 is 139/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
84/36 = 84 × 7/36 × 7 = 588/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
90/21 = 90 × 12/21 × 12 = 1080/252 - Add the two like fractions:
588/252 + 1080/252 = 588 + 1080/252 = 1668/252 - 1668/252 simplified gives 139/21
- So, 84/36 + 90/21 = 139/21
In mixed form: 613/21
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