Subtract 21/8 from 54/90
1st number: 54/90, 2nd number: 2 5/8
54/90 - 21/8 is -81/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
54/90 = 54 × 4/90 × 4 = 216/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Subtract the two like fractions:
216/360 - 945/360 = 216 - 945/360 = -729/360 - After reducing the fraction, the answer is -81/40
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