Subtract 20/32 from 7/81
7/81 - 20/32 is -349/648.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 32 is 2592
Next, find the equivalent fraction of both fractional numbers with denominator 2592 - For the 1st fraction, since 81 × 32 = 2592,
7/81 = 7 × 32/81 × 32 = 224/2592 - Likewise, for the 2nd fraction, since 32 × 81 = 2592,
20/32 = 20 × 81/32 × 81 = 1620/2592 - Subtract the two like fractions:
224/2592 - 1620/2592 = 224 - 1620/2592 = -1396/2592 - After reducing the fraction, the answer is -349/648
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