Subtract 72/90 from 75/21
1st number: 3 12/21, 2nd number: 72/90
75/21 - 72/90 is 97/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
75/21 = 75 × 30/21 × 30 = 2250/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Subtract the two like fractions:
2250/630 - 504/630 = 2250 - 504/630 = 1746/630 - After reducing the fraction, the answer is 97/35
- In mixed form: 227/35
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