Subtract 81/70 from 3/72
1st number: 3/72, 2nd number: 1 11/70
3/72 - 81/70 is -937/840.
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,
3/72 = 3 × 35/72 × 35 = 105/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
81/70 = 81 × 36/70 × 36 = 2916/2520 - Subtract the two like fractions:
105/2520 - 2916/2520 = 105 - 2916/2520 = -2811/2520 - After reducing the fraction, the answer is -937/840
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