Subtract 40/70 from 30/63
30/63 - 40/70 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
30/63 = 30 × 10/63 × 10 = 300/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
40/70 = 40 × 9/70 × 9 = 360/630 - Subtract the two like fractions:
300/630 - 360/630 = 300 - 360/630 = -60/630 - After reducing the fraction, the answer is -2/21
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