Subtract 21/45 from 7/20
7/20 - 21/45 is -7/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
7/20 = 7 × 9/20 × 9 = 63/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180 - Subtract the two like fractions:
63/180 - 84/180 = 63 - 84/180 = -21/180 - After reducing the fraction, the answer is -7/60
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