Subtract 90/72 from 42/75
1st number: 42/75, 2nd number: 1 18/72
42/75 - 90/72 is -69/100.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 72 is 1800
Next, find the equivalent fraction of both fractional numbers with denominator 1800 - For the 1st fraction, since 75 × 24 = 1800,
42/75 = 42 × 24/75 × 24 = 1008/1800 - Likewise, for the 2nd fraction, since 72 × 25 = 1800,
90/72 = 90 × 25/72 × 25 = 2250/1800 - Subtract the two like fractions:
1008/1800 - 2250/1800 = 1008 - 2250/1800 = -1242/1800 - After reducing the fraction, the answer is -69/100
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