Subtract 18/90 from 72/21
1st number: 3 9/21, 2nd number: 18/90
72/21 - 18/90 is 113/35.
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,
72/21 = 72 × 30/21 × 30 = 2160/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630 - Subtract the two like fractions:
2160/630 - 126/630 = 2160 - 126/630 = 2034/630 - After reducing the fraction, the answer is 113/35
- In mixed form: 38/35
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