Subtract 21/40 from 90/72
1st number: 1 18/72, 2nd number: 21/40
90/72 - 21/40 is 29/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Subtract the two like fractions:
450/360 - 189/360 = 450 - 189/360 = 261/360 - After reducing the fraction, the answer is 29/40
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