Subtract 18/30 from 21/64
21/64 - 18/30 is -87/320.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 64 and 30 is 960
Next, find the equivalent fraction of both fractional numbers with denominator 960 - For the 1st fraction, since 64 × 15 = 960,
21/64 = 21 × 15/64 × 15 = 315/960 - Likewise, for the 2nd fraction, since 30 × 32 = 960,
18/30 = 18 × 32/30 × 32 = 576/960 - Subtract the two like fractions:
315/960 - 576/960 = 315 - 576/960 = -261/960 - After reducing the fraction, the answer is -87/320
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