Subtract 90/21 from 72/8
1st number: 9 0/8, 2nd number: 4 6/21
72/8 - 90/21 is 33/7.
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,
72/8 = 72 × 21/8 × 21 = 1512/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168 - Subtract the two like fractions:
1512/168 - 720/168 = 1512 - 720/168 = 792/168 - After reducing the fraction, the answer is 33/7
- In mixed form: 45/7
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