Subtract 21/90 from 4/63
4/63 - 21/90 is -107/630.
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,
4/63 = 4 × 10/63 × 10 = 40/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Subtract the two like fractions:
40/630 - 147/630 = 40 - 147/630 = -107/630
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