Subtract 3/18 from 21/30
21/30 - 3/18 is 8/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
3/18 = 3 × 5/18 × 5 = 15/90 - Subtract the two like fractions:
63/90 - 15/90 = 63 - 15/90 = 48/90 - After reducing the fraction, the answer is 8/15
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