Subtract 75/21 from 70/20
1st number: 3 10/20, 2nd number: 3 12/21
70/20 - 75/21 is -1/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
75/21 = 75 × 20/21 × 20 = 1500/420 - Subtract the two like fractions:
1470/420 - 1500/420 = 1470 - 1500/420 = -30/420 - After reducing the fraction, the answer is -1/14
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