Subtract 9/16 from 21/90
21/90 - 9/16 is -79/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 16 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 16 × 45 = 720,
9/16 = 9 × 45/16 × 45 = 405/720 - Subtract the two like fractions:
168/720 - 405/720 = 168 - 405/720 = -237/720 - After reducing the fraction, the answer is -79/240
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