Subtract 70/50 from 18/21
1st number: 18/21, 2nd number: 1 20/50
18/21 - 70/50 is -19/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 50 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 21 × 50 = 1050,
18/21 = 18 × 50/21 × 50 = 900/1050 - Likewise, for the 2nd fraction, since 50 × 21 = 1050,
70/50 = 70 × 21/50 × 21 = 1470/1050 - Subtract the two like fractions:
900/1050 - 1470/1050 = 900 - 1470/1050 = -570/1050 - After reducing the fraction, the answer is -19/35
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