Subtract 90/72 from 42/70
1st number: 42/70, 2nd number: 1 18/72
42/70 - 90/72 is -13/20.
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,
42/70 = 42 × 36/70 × 36 = 1512/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
90/72 = 90 × 35/72 × 35 = 3150/2520 - Subtract the two like fractions:
1512/2520 - 3150/2520 = 1512 - 3150/2520 = -1638/2520 - After reducing the fraction, the answer is -13/20
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Related: 84/70-90/72