Subtract 7/90 from 18/21
18/21 - 7/90 is 491/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
18/21 = 18 × 30/21 × 30 = 540/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
7/90 = 7 × 7/90 × 7 = 49/630 - Subtract the two like fractions:
540/630 - 49/630 = 540 - 49/630 = 491/630
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