Subtract 70/45 from 42/81
1st number: 42/81, 2nd number: 1 25/45
42/81 - 70/45 is -28/27.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
42/81 = 42 × 5/81 × 5 = 210/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
70/45 = 70 × 9/45 × 9 = 630/405 - Subtract the two like fractions:
210/405 - 630/405 = 210 - 630/405 = -420/405 - After reducing the fraction, the answer is -28/27
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