Subtract 21/45 from 1/2
1/2 - 21/45 is 1/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 2 × 45 = 90,
1/2 = 1 × 45/2 × 45 = 45/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Subtract the two like fractions:
45/90 - 42/90 = 45 - 42/90 = 3/90 - After reducing the fraction, the answer is 1/30
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