Subtract 15/42 from 7/90
7/90 - 15/42 is -88/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
7/90 = 7 × 7/90 × 7 = 49/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
15/42 = 15 × 15/42 × 15 = 225/630 - Subtract the two like fractions:
49/630 - 225/630 = 49 - 225/630 = -176/630 - After reducing the fraction, the answer is -88/315
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