Subtract 5/42 from 15/40
15/40 - 5/42 is 43/168.
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,
15/40 = 15 × 21/40 × 21 = 315/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
5/42 = 5 × 20/42 × 20 = 100/840 - Subtract the two like fractions:
315/840 - 100/840 = 315 - 100/840 = 215/840 - After reducing the fraction, the answer is 43/168
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