Subtract 21/32 from 40/42
40/42 - 21/32 is 199/672.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 32 is 672
Next, find the equivalent fraction of both fractional numbers with denominator 672 - For the 1st fraction, since 42 × 16 = 672,
40/42 = 40 × 16/42 × 16 = 640/672 - Likewise, for the 2nd fraction, since 32 × 21 = 672,
21/32 = 21 × 21/32 × 21 = 441/672 - Subtract the two like fractions:
640/672 - 441/672 = 640 - 441/672 = 199/672
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