Subtract 21/45 from 18/70
18/70 - 21/45 is -22/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
18/70 = 18 × 9/70 × 9 = 162/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630 - Subtract the two like fractions:
162/630 - 294/630 = 162 - 294/630 = -132/630 - After reducing the fraction, the answer is -22/105
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