Add 90/12 and 42/21
1st number: 7 6/12, 2nd number: 2 0/21
90/12 + 42/21 is 19/2.
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,
42/21 = 42 × 4/21 × 4 = 168/84 - Add the two like fractions:
630/84 + 168/84 = 630 + 168/84 = 798/84 - 798/84 simplified gives 19/2
- So, 90/12 + 42/21 = 19/2
In mixed form: 91/2
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