Subtract 21/42 from 20/32
20/32 - 21/42 is 1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 32 and 42 is 672
Next, find the equivalent fraction of both fractional numbers with denominator 672 - For the 1st fraction, since 32 × 21 = 672,
20/32 = 20 × 21/32 × 21 = 420/672 - Likewise, for the 2nd fraction, since 42 × 16 = 672,
21/42 = 21 × 16/42 × 16 = 336/672 - Subtract the two like fractions:
420/672 - 336/672 = 420 - 336/672 = 84/672 - After reducing the fraction, the answer is 1/8
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