Subtract 84/36 from 21/90
1st number: 21/90, 2nd number: 2 12/36
21/90 - 84/36 is -21/10.
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,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
84/36 = 84 × 5/36 × 5 = 420/180 - Subtract the two like fractions:
42/180 - 420/180 = 42 - 420/180 = -378/180 - After reducing the fraction, the answer is -21/10
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