Subtract 21/9 from 45/70
1st number: 45/70, 2nd number: 2 3/9
45/70 - 21/9 is -71/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
45/70 = 45 × 9/70 × 9 = 405/630 - Likewise, for the 2nd fraction, since 9 × 70 = 630,
21/9 = 21 × 70/9 × 70 = 1470/630 - Subtract the two like fractions:
405/630 - 1470/630 = 405 - 1470/630 = -1065/630 - After reducing the fraction, the answer is -71/42
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