Subtract 20/15 from 75/21
1st number: 3 12/21, 2nd number: 1 5/15
75/21 - 20/15 is 47/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
75/21 = 75 × 5/21 × 5 = 375/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
20/15 = 20 × 7/15 × 7 = 140/105 - Subtract the two like fractions:
375/105 - 140/105 = 375 - 140/105 = 235/105 - After reducing the fraction, the answer is 47/21
- In mixed form: 25/21
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