Subtract 18/90 from 7/63
7/63 - 18/90 is -4/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
7/63 = 7 × 10/63 × 10 = 70/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630 - Subtract the two like fractions:
70/630 - 126/630 = 70 - 126/630 = -56/630 - After reducing the fraction, the answer is -4/45
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