Subtract 30/45 from 10/42
10/42 - 30/45 is -3/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 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 45 × 14 = 630,
30/45 = 30 × 14/45 × 14 = 420/630 - Subtract the two like fractions:
150/630 - 420/630 = 150 - 420/630 = -270/630 - After reducing the fraction, the answer is -3/7
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