Subtract 28/30 from 21/50
21/50 - 28/30 is -77/150.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 30 is 150
Next, find the equivalent fraction of both fractional numbers with denominator 150 - For the 1st fraction, since 50 × 3 = 150,
21/50 = 21 × 3/50 × 3 = 63/150 - Likewise, for the 2nd fraction, since 30 × 5 = 150,
28/30 = 28 × 5/30 × 5 = 140/150 - Subtract the two like fractions:
63/150 - 140/150 = 63 - 140/150 = -77/150
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