Subtract 12/40 from 40/42
40/42 - 12/40 is 137/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
40/42 = 40 × 20/42 × 20 = 800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Subtract the two like fractions:
800/840 - 252/840 = 800 - 252/840 = 548/840 - After reducing the fraction, the answer is 137/210
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