Add 90/54 and 72/21
1st number: 1 36/54, 2nd number: 3 9/21
90/54 + 72/21 is 107/21.
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,
72/21 = 72 × 18/21 × 18 = 1296/378 - Add the two like fractions:
630/378 + 1296/378 = 630 + 1296/378 = 1926/378 - 1926/378 simplified gives 107/21
- So, 90/54 + 72/21 = 107/21
In mixed form: 52/21
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