Subtract 28/21 from 45/70
1st number: 45/70, 2nd number: 1 7/21
45/70 - 28/21 is -29/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
45/70 = 45 × 3/70 × 3 = 135/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Subtract the two like fractions:
135/210 - 280/210 = 135 - 280/210 = -145/210 - After reducing the fraction, the answer is -29/42
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