Subtract 4/90 from 3/70
3/70 - 4/90 is -1/630.
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,
3/70 = 3 × 9/70 × 9 = 27/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
4/90 = 4 × 7/90 × 7 = 28/630 - Subtract the two like fractions:
27/630 - 28/630 = 27 - 28/630 = -1/630
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