Subtract 8/42 from 7/45
7/45 - 8/42 is -11/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
7/45 = 7 × 14/45 × 14 = 98/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
8/42 = 8 × 15/42 × 15 = 120/630 - Subtract the two like fractions:
98/630 - 120/630 = 98 - 120/630 = -22/630 - After reducing the fraction, the answer is -11/315
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