Subtract 49/40 from 20/81
1st number: 20/81, 2nd number: 1 9/40
20/81 - 49/40 is -3169/3240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 40 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 81 × 40 = 3240,
20/81 = 20 × 40/81 × 40 = 800/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
49/40 = 49 × 81/40 × 81 = 3969/3240 - Subtract the two like fractions:
800/3240 - 3969/3240 = 800 - 3969/3240 = -3169/3240
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