Add 1/21 and 90/54
1st number: 1/21, 2nd number: 1 36/54
1/21 + 90/54 is 12/7.
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,
1/21 = 1 × 18/21 × 18 = 18/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
90/54 = 90 × 7/54 × 7 = 630/378 - Add the two like fractions:
18/378 + 630/378 = 18 + 630/378 = 648/378 - 648/378 simplified gives 12/7
- So, 1/21 + 90/54 = 12/7
In mixed form: 15/7
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