Subtract 18/72 from 72/21
1st number: 3 9/21, 2nd number: 18/72
72/21 - 18/72 is 89/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
72/21 = 72 × 24/21 × 24 = 1728/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Subtract the two like fractions:
1728/504 - 126/504 = 1728 - 126/504 = 1602/504 - After reducing the fraction, the answer is 89/28
- In mixed form: 35/28
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