Subtract 30/90 from 8/70
8/70 - 30/90 is -23/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
8/70 = 8 × 9/70 × 9 = 72/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
30/90 = 30 × 7/90 × 7 = 210/630 - Subtract the two like fractions:
72/630 - 210/630 = 72 - 210/630 = -138/630 - After reducing the fraction, the answer is -23/105
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