Subtract 36/40 from 30/42
30/42 - 36/40 is -13/70.
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,
30/42 = 30 × 20/42 × 20 = 600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
36/40 = 36 × 21/40 × 21 = 756/840 - Subtract the two like fractions:
600/840 - 756/840 = 600 - 756/840 = -156/840 - After reducing the fraction, the answer is -13/70
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