Subtract 21/4 from 90/45
1st number: 2 0/45, 2nd number: 5 1/4
90/45 - 21/4 is -13/4.
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,
90/45 = 90 × 4/45 × 4 = 360/180 - Likewise, for the 2nd fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180 - Subtract the two like fractions:
360/180 - 945/180 = 360 - 945/180 = -585/180 - After reducing the fraction, the answer is -13/4
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