Subtract 21/4 from 7/45
1st number: 7/45, 2nd number: 5 1/4
7/45 - 21/4 is -917/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 4 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
7/45 = 7 × 4/45 × 4 = 28/180 - Likewise, for the 2nd fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180 - Subtract the two like fractions:
28/180 - 945/180 = 28 - 945/180 = -917/180
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