Subtract 30/63 from 30/70
30/70 - 30/63 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
30/70 = 30 × 9/70 × 9 = 270/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
30/63 = 30 × 10/63 × 10 = 300/630 - Subtract the two like fractions:
270/630 - 300/630 = 270 - 300/630 = -30/630 - After reducing the fraction, the answer is -1/21
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