Subtract 90/70 from 81/72
1st number: 1 9/72, 2nd number: 1 20/70
81/72 - 90/70 is -9/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
81/72 = 81 × 35/72 × 35 = 2835/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
90/70 = 90 × 36/70 × 36 = 3240/2520 - Subtract the two like fractions:
2835/2520 - 3240/2520 = 2835 - 3240/2520 = -405/2520 - After reducing the fraction, the answer is -9/56
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