Add 90/12 and 40/21
1st number: 7 6/12, 2nd number: 1 19/21
90/12 + 40/21 is 395/42.
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,
90/12 = 90 × 7/12 × 7 = 630/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
40/21 = 40 × 4/21 × 4 = 160/84 - Add the two like fractions:
630/84 + 160/84 = 630 + 160/84 = 790/84 - 790/84 simplified gives 395/42
- So, 90/12 + 40/21 = 395/42
In mixed form: 917/42
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