Subtract 90/72 from 21/60
1st number: 21/60, 2nd number: 1 18/72
21/60 - 90/72 is -9/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 60 × 6 = 360,
21/60 = 21 × 6/60 × 6 = 126/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Subtract the two like fractions:
126/360 - 450/360 = 126 - 450/360 = -324/360 - After reducing the fraction, the answer is -9/10
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