Subtract 42/10 from 81/21
1st number: 3 18/21, 2nd number: 4 2/10
81/21 - 42/10 is -12/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
42/10 = 42 × 21/10 × 21 = 882/210 - Subtract the two like fractions:
810/210 - 882/210 = 810 - 882/210 = -72/210 - After reducing the fraction, the answer is -12/35
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