Subtract 10/81 from 4/40, Solve 4/40

Subtract 10/81 from 4/40

4/40 - 10/81 is -19/810.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240

Next, find the equivalent fraction of both fractional numbers with denominator 3240
For the 1st fraction, since 40 × 81 = 3240,
4/40 = 4 × 81/40 × 81 = 324/3240
Likewise, for the 2nd fraction, since 81 × 40 = 3240,
10/81 = 10 × 40/81 × 40 = 400/3240
Subtract the two like fractions:
324/3240 - 400/3240 = 324 - 400/3240 = -76/3240
After reducing the fraction, the answer is -19/810

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