Subtract 21/90 from 27/40, Solve 27/40

Subtract 21/90 from 27/40

27/40 - 21/90 is 53/120.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 40 × 9 = 360,
27/40 = 27 × 9/40 × 9 = 243/360
Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360
Subtract the two like fractions:
243/360 - 84/360 = 243 - 84/360 = 159/360
After reducing the fraction, the answer is 53/120

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