Subtract 90/84 from 42/40
1st number: 1 2/40, 2nd number: 1 6/84
42/40 - 90/84 is -3/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 84 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840 - Likewise, for the 2nd fraction, since 84 × 10 = 840,
90/84 = 90 × 10/84 × 10 = 900/840 - Subtract the two like fractions:
882/840 - 900/840 = 882 - 900/840 = -18/840 - After reducing the fraction, the answer is -3/140
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