Subtract 9/72 from 21/8
1st number: 2 5/8, 2nd number: 9/72
21/8 - 9/72 is 5/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
9/72 = 9 × 1/72 × 1 = 9/72 - Subtract the two like fractions:
189/72 - 9/72 = 189 - 9/72 = 180/72 - After reducing the fraction, the answer is 5/2
- In mixed form: 21/2
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