Subtract 90/21 from 45/8
1st number: 5 5/8, 2nd number: 4 6/21
45/8 - 90/21 is 75/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
45/8 = 45 × 21/8 × 21 = 945/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168 - Subtract the two like fractions:
945/168 - 720/168 = 945 - 720/168 = 225/168 - After reducing the fraction, the answer is 75/56
- In mixed form: 119/56
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