Subtract 90/72 from 25/21
1st number: 1 4/21, 2nd number: 1 18/72
25/21 - 90/72 is -5/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
25/21 = 25 × 24/21 × 24 = 600/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Subtract the two like fractions:
600/504 - 630/504 = 600 - 630/504 = -30/504 - After reducing the fraction, the answer is -5/84
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