Subtract 90/70 from 12/45
1st number: 12/45, 2nd number: 1 20/70
12/45 - 90/70 is -107/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
12/45 = 12 × 14/45 × 14 = 168/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630 - Subtract the two like fractions:
168/630 - 810/630 = 168 - 810/630 = -642/630 - After reducing the fraction, the answer is -107/105
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