Subtract 40/21 from 40/90
1st number: 40/90, 2nd number: 1 19/21
40/90 - 40/21 is -92/63.
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,
40/90 = 40 × 7/90 × 7 = 280/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
40/21 = 40 × 30/21 × 30 = 1200/630 - Subtract the two like fractions:
280/630 - 1200/630 = 280 - 1200/630 = -920/630 - After reducing the fraction, the answer is -92/63
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