Add 90/54 and 40/21
1st number: 1 36/54, 2nd number: 1 19/21
90/54 + 40/21 is 25/7.
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,
40/21 = 40 × 18/21 × 18 = 720/378 - Add the two like fractions:
630/378 + 720/378 = 630 + 720/378 = 1350/378 - 1350/378 simplified gives 25/7
- So, 90/54 + 40/21 = 25/7
In mixed form: 34/7
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