Subtract 1/90 from 45/72
45/72 - 1/90 is 221/360.
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,
45/72 = 45 × 5/72 × 5 = 225/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
1/90 = 1 × 4/90 × 4 = 4/360 - Subtract the two like fractions:
225/360 - 4/360 = 225 - 4/360 = 221/360
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