Subtract 70/81 from 28/72
28/72 - 70/81 is -77/162.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
28/72 = 28 × 9/72 × 9 = 252/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
70/81 = 70 × 8/81 × 8 = 560/648 - Subtract the two like fractions:
252/648 - 560/648 = 252 - 560/648 = -308/648 - After reducing the fraction, the answer is -77/162
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