Subtract 81/45 from 21/70
1st number: 21/70, 2nd number: 1 36/45
21/70 - 81/45 is -3/2.
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,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
81/45 = 81 × 14/45 × 14 = 1134/630 - Subtract the two like fractions:
189/630 - 1134/630 = 189 - 1134/630 = -945/630 - After reducing the fraction, the answer is -3/2
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