Subtract 81/72 from 28/70
1st number: 28/70, 2nd number: 1 9/72
28/70 - 81/72 is -29/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
28/70 = 28 × 36/70 × 36 = 1008/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
81/72 = 81 × 35/72 × 35 = 2835/2520 - Subtract the two like fractions:
1008/2520 - 2835/2520 = 1008 - 2835/2520 = -1827/2520 - After reducing the fraction, the answer is -29/40
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