Subtract 21/72 from 90/42
1st number: 2 6/42, 2nd number: 21/72
90/42 - 21/72 is 311/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
90/42 = 90 × 12/42 × 12 = 1080/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Subtract the two like fractions:
1080/504 - 147/504 = 1080 - 147/504 = 933/504 - After reducing the fraction, the answer is 311/168
- In mixed form: 1143/168
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