Add 42/21 and 90/54
1st number: 2 0/21, 2nd number: 1 36/54
42/21 + 90/54 is 11/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
42/21 = 42 × 18/21 × 18 = 756/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
90/54 = 90 × 7/54 × 7 = 630/378 - Add the two like fractions:
756/378 + 630/378 = 756 + 630/378 = 1386/378 - 1386/378 simplified gives 11/3
- So, 42/21 + 90/54 = 11/3
In mixed form: 32/3
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