Subtract 21/81 from 45/36, Solve 1 9/36

Subtract 21/81 from 45/36

1^st number: 1 9/36, 2^nd number: 21/81

45/36 - 21/81 is 107/108.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 81 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 36 × 9 = 324,
45/36 = 45 × 9/36 × 9 = 405/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324
Subtract the two like fractions:
405/324 - 84/324 = 405 - 84/324 = 321/324
After reducing the fraction, the answer is 107/108

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