Subtract 40/36 from 21/8
1st number: 2 5/8, 2nd number: 1 4/36
21/8 - 40/36 is 109/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 36 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 36 × 2 = 72,
40/36 = 40 × 2/36 × 2 = 80/72 - Subtract the two like fractions:
189/72 - 80/72 = 189 - 80/72 = 109/72 - In mixed form: 137/72
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