Subtract 21/81 from 42/30
1st number: 1 12/30, 2nd number: 21/81
42/30 - 21/81 is 154/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
42/30 = 42 × 27/30 × 27 = 1134/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
21/81 = 21 × 10/81 × 10 = 210/810 - Subtract the two like fractions:
1134/810 - 210/810 = 1134 - 210/810 = 924/810 - After reducing the fraction, the answer is 154/135
- In mixed form: 119/135
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