Subtract 42/45 from 16/20
16/20 - 42/45 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
16/20 = 16 × 9/20 × 9 = 144/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Subtract the two like fractions:
144/180 - 168/180 = 144 - 168/180 = -24/180 - After reducing the fraction, the answer is -2/15
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