Subtract 18/20 from 28/49
28/49 - 18/20 is -23/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 20 is 980
Next, find the equivalent fraction of both fractional numbers with denominator 980 - For the 1st fraction, since 49 × 20 = 980,
28/49 = 28 × 20/49 × 20 = 560/980 - Likewise, for the 2nd fraction, since 20 × 49 = 980,
18/20 = 18 × 49/20 × 49 = 882/980 - Subtract the two like fractions:
560/980 - 882/980 = 560 - 882/980 = -322/980 - After reducing the fraction, the answer is -23/70
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