Subtract 15/70 from 3/90
3/90 - 15/70 is -19/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
3/90 = 3 × 7/90 × 7 = 21/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
15/70 = 15 × 9/70 × 9 = 135/630 - Subtract the two like fractions:
21/630 - 135/630 = 21 - 135/630 = -114/630 - After reducing the fraction, the answer is -19/105
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