Subtract 21/10 from 18/84
1st number: 18/84, 2nd number: 2 1/10
18/84 - 21/10 is -66/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 10 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420 - Likewise, for the 2nd fraction, since 10 × 42 = 420,
21/10 = 21 × 42/10 × 42 = 882/420 - Subtract the two like fractions:
90/420 - 882/420 = 90 - 882/420 = -792/420 - After reducing the fraction, the answer is -66/35
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