Subtract 90/72 from 5/7
1st number: 5/7, 2nd number: 1 18/72
5/7 - 90/72 is -15/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 7 × 72 = 504,
5/7 = 5 × 72/7 × 72 = 360/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Subtract the two like fractions:
360/504 - 630/504 = 360 - 630/504 = -270/504 - After reducing the fraction, the answer is -15/28
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