Subtract 18/16 from 21/30
1st number: 21/30, 2nd number: 1 2/16
21/30 - 18/16 is -17/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 16 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 30 × 8 = 240,
21/30 = 21 × 8/30 × 8 = 168/240 - Likewise, for the 2nd fraction, since 16 × 15 = 240,
18/16 = 18 × 15/16 × 15 = 270/240 - Subtract the two like fractions:
168/240 - 270/240 = 168 - 270/240 = -102/240 - After reducing the fraction, the answer is -17/40
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