Subtract 21/45 from 2/5
2/5 - 21/45 is -1/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 45 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 5 × 9 = 45,
2/5 = 2 × 9/5 × 9 = 18/45 - Likewise, for the 2nd fraction, since 45 × 1 = 45,
21/45 = 21 × 1/45 × 1 = 21/45 - Subtract the two like fractions:
18/45 - 21/45 = 18 - 21/45 = -3/45 - After reducing the fraction, the answer is -1/15
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