Subtract 21/15 from 42/90
1st number: 42/90, 2nd number: 1 6/15
42/90 - 21/15 is -14/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 15 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Likewise, for the 2nd fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Subtract the two like fractions:
42/90 - 126/90 = 42 - 126/90 = -84/90 - After reducing the fraction, the answer is -14/15
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