Subtract 42/21 from 15/90
1st number: 15/90, 2nd number: 2 0/21
15/90 - 42/21 is -11/6.
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,
15/90 = 15 × 7/90 × 7 = 105/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630 - Subtract the two like fractions:
105/630 - 1260/630 = 105 - 1260/630 = -1155/630 - After reducing the fraction, the answer is -11/6
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