Subtract 21/8 from 42/45
1st number: 42/45, 2nd number: 2 5/8
42/45 - 21/8 is -203/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
42/45 = 42 × 8/45 × 8 = 336/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Subtract the two like fractions:
336/360 - 945/360 = 336 - 945/360 = -609/360 - After reducing the fraction, the answer is -203/120
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