Subtract 9/42 from 90/72
1st number: 1 18/72, 2nd number: 9/42
90/72 - 9/42 is 29/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Likewise, for the 2nd fraction, since 42 × 12 = 504,
9/42 = 9 × 12/42 × 12 = 108/504 - Subtract the two like fractions:
630/504 - 108/504 = 630 - 108/504 = 522/504 - After reducing the fraction, the answer is 29/28
- In mixed form: 11/28
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