Add 3/12 and 90/21
1st number: 3/12, 2nd number: 4 6/21
3/12 + 90/21 is 127/28.
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,
3/12 = 3 × 7/12 × 7 = 21/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Add the two like fractions:
21/84 + 360/84 = 21 + 360/84 = 381/84 - 381/84 simplified gives 127/28
- So, 3/12 + 90/21 = 127/28
In mixed form: 415/28
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