Subtract 15/27 from 90/21, Solve 4 6/21

Subtract 15/27 from 90/21

1^st number: 4 6/21, 2^nd number: 15/27

90/21 - 15/27 is 235/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
90/21 = 90 × 9/21 × 9 = 810/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
15/27 = 15 × 7/27 × 7 = 105/189
Subtract the two like fractions:
810/189 - 105/189 = 810 - 105/189 = 705/189
After reducing the fraction, the answer is 235/63
In mixed form: 346/63

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