Subtract 72/90 from 25/42
25/42 - 72/90 is -43/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
25/42 = 25 × 15/42 × 15 = 375/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Subtract the two like fractions:
375/630 - 504/630 = 375 - 504/630 = -129/630 - After reducing the fraction, the answer is -43/210
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