Subtract 21/9 from 81/15, Solve 5 6/15

Subtract 21/9 from 81/15

1^st number: 5 6/15, 2^nd number: 2 3/9

81/15 - 21/9 is 46/15.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 9 is 45

Next, find the equivalent fraction of both fractional numbers with denominator 45
For the 1st fraction, since 15 × 3 = 45,
81/15 = 81 × 3/15 × 3 = 243/45
Likewise, for the 2nd fraction, since 9 × 5 = 45,
21/9 = 21 × 5/9 × 5 = 105/45
Subtract the two like fractions:
243/45 - 105/45 = 243 - 105/45 = 138/45
After reducing the fraction, the answer is 46/15
In mixed form: 31/15

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