Subtract 90/72 from 90/20
1st number: 4 10/20, 2nd number: 1 18/72
90/20 - 90/72 is 13/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
90/20 = 90 × 18/20 × 18 = 1620/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Subtract the two like fractions:
1620/360 - 450/360 = 1620 - 450/360 = 1170/360 - After reducing the fraction, the answer is 13/4
- In mixed form: 31/4
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