Subtract 18/20 from 42/64
42/64 - 18/20 is -39/160.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 64 and 20 is 320
Next, find the equivalent fraction of both fractional numbers with denominator 320 - For the 1st fraction, since 64 × 5 = 320,
42/64 = 42 × 5/64 × 5 = 210/320 - Likewise, for the 2nd fraction, since 20 × 16 = 320,
18/20 = 18 × 16/20 × 16 = 288/320 - Subtract the two like fractions:
210/320 - 288/320 = 210 - 288/320 = -78/320 - After reducing the fraction, the answer is -39/160
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