Subtract 9/63 from 90/21, Solve 4 6/21

Subtract 9/63 from 90/21

1^st number: 4 6/21, 2^nd number: 9/63

90/21 - 9/63 is 29/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
90/21 = 90 × 3/21 × 3 = 270/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
9/63 = 9 × 1/63 × 1 = 9/63
Subtract the two like fractions:
270/63 - 9/63 = 270 - 9/63 = 261/63
After reducing the fraction, the answer is 29/7
In mixed form: 41/7

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