Subtract 5/7 from 42/9, Solve 4 6/9

Subtract 5/7 from 42/9

1^st number: 4 6/9, 2^nd number: 5/7

42/9 - 5/7 is 83/21.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 7 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 7 × 9 = 63,
5/7 = 5 × 9/7 × 9 = 45/63
Subtract the two like fractions:
294/63 - 45/63 = 294 - 45/63 = 249/63
After reducing the fraction, the answer is 83/21
In mixed form: 320/21

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