Add 84/12 and 90/21
1st number: 7 0/12, 2nd number: 4 6/21
84/12 + 90/21 is 79/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
84/12 = 84 × 7/12 × 7 = 588/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Add the two like fractions:
588/84 + 360/84 = 588 + 360/84 = 948/84 - 948/84 simplified gives 79/7
- So, 84/12 + 90/21 = 79/7
In mixed form: 112/7
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