Subtract 72/21 from 90/5
1st number: 18 0/5, 2nd number: 3 9/21
90/5 - 72/21 is 102/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
90/5 = 90 × 21/5 × 21 = 1890/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
72/21 = 72 × 5/21 × 5 = 360/105 - Subtract the two like fractions:
1890/105 - 360/105 = 1890 - 360/105 = 1530/105 - After reducing the fraction, the answer is 102/7
- In mixed form: 144/7
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