Subtract 30/70 from 15/45
15/45 - 30/70 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
15/45 = 15 × 14/45 × 14 = 210/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
30/70 = 30 × 9/70 × 9 = 270/630 - Subtract the two like fractions:
210/630 - 270/630 = 210 - 270/630 = -60/630 - After reducing the fraction, the answer is -2/21
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