Subtract 9/42 from 2/40
2/40 - 9/42 is -23/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
2/40 = 2 × 21/40 × 21 = 42/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
9/42 = 9 × 20/42 × 20 = 180/840 - Subtract the two like fractions:
42/840 - 180/840 = 42 - 180/840 = -138/840 - After reducing the fraction, the answer is -23/140
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