Subtract 21/36 from 42/90
42/90 - 21/36 is -7/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
42/90 = 42 × 2/90 × 2 = 84/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Subtract the two like fractions:
84/180 - 105/180 = 84 - 105/180 = -21/180 - After reducing the fraction, the answer is -7/60
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