Subtract 72/40 from 21/6
1st number: 3 3/6, 2nd number: 1 32/40
21/6 - 72/40 is 17/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 6 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 6 × 20 = 120,
21/6 = 21 × 20/6 × 20 = 420/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
72/40 = 72 × 3/40 × 3 = 216/120 - Subtract the two like fractions:
420/120 - 216/120 = 420 - 216/120 = 204/120 - After reducing the fraction, the answer is 17/10
- In mixed form: 17/10
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