Subtract 10/21 from 9/90
9/90 - 10/21 is -79/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
9/90 = 9 × 7/90 × 7 = 63/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
10/21 = 10 × 30/21 × 30 = 300/630 - Subtract the two like fractions:
63/630 - 300/630 = 63 - 300/630 = -237/630 - After reducing the fraction, the answer is -79/210
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