Subtract 1/90 from 12/21
12/21 - 1/90 is 353/630.
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,
12/21 = 12 × 30/21 × 30 = 360/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
1/90 = 1 × 7/90 × 7 = 7/630 - Subtract the two like fractions:
360/630 - 7/630 = 360 - 7/630 = 353/630
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