Subtract 21/90 from 42/30
1st number: 1 12/30, 2nd number: 21/90
42/30 - 21/90 is 7/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
42/30 = 42 × 3/30 × 3 = 126/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
126/90 - 21/90 = 126 - 21/90 = 105/90 - After reducing the fraction, the answer is 7/6
- In mixed form: 11/6
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