Subtract 90/21 from 42/10
1st number: 4 2/10, 2nd number: 4 6/21
42/10 - 90/21 is -3/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
42/10 = 42 × 21/10 × 21 = 882/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
90/21 = 90 × 10/21 × 10 = 900/210 - Subtract the two like fractions:
882/210 - 900/210 = 882 - 900/210 = -18/210 - After reducing the fraction, the answer is -3/35
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