Subtract 30/90 from 10/42
10/42 - 30/90 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
10/42 = 10 × 15/42 × 15 = 150/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
30/90 = 30 × 7/90 × 7 = 210/630 - Subtract the two like fractions:
150/630 - 210/630 = 150 - 210/630 = -60/630 - After reducing the fraction, the answer is -2/21
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