Subtract 42/40 from 7/84
1st number: 7/84, 2nd number: 1 2/40
7/84 - 42/40 is -29/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
7/84 = 7 × 10/84 × 10 = 70/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840 - Subtract the two like fractions:
70/840 - 882/840 = 70 - 882/840 = -812/840 - After reducing the fraction, the answer is -29/30
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