Subtract 3/21 from 42/9, Solve 4 6/9

Subtract 3/21 from 42/9

1^st number: 4 6/9, 2^nd number: 3/21

42/9 - 3/21 is 95/21.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
3/21 = 3 × 3/21 × 3 = 9/63
Subtract the two like fractions:
294/63 - 9/63 = 294 - 9/63 = 285/63
After reducing the fraction, the answer is 95/21
In mixed form: 411/21

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