Add 90/54 and 80/21
1st number: 1 36/54, 2nd number: 3 17/21
90/54 + 80/21 is 115/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
90/54 = 90 × 7/54 × 7 = 630/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
80/21 = 80 × 18/21 × 18 = 1440/378 - Add the two like fractions:
630/378 + 1440/378 = 630 + 1440/378 = 2070/378 - 2070/378 simplified gives 115/21
- So, 90/54 + 80/21 = 115/21
In mixed form: 510/21
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