Add 72/21 and 36/54
1st number: 3 9/21, 2nd number: 36/54
72/21 + 36/54 is 86/21.
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,
72/21 = 72 × 18/21 × 18 = 1296/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
36/54 = 36 × 7/54 × 7 = 252/378 - Add the two like fractions:
1296/378 + 252/378 = 1296 + 252/378 = 1548/378 - 1548/378 simplified gives 86/21
- So, 72/21 + 36/54 = 86/21
In mixed form: 42/21
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