Subtract 9/90 from 7/72
7/72 - 9/90 is -1/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
7/72 = 7 × 5/72 × 5 = 35/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
9/90 = 9 × 4/90 × 4 = 36/360 - Subtract the two like fractions:
35/360 - 36/360 = 35 - 36/360 = -1/360
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