Subtract 20/28 from 42/9, Solve 4 6/9

Subtract 20/28 from 42/9

1^st number: 4 6/9, 2^nd number: 20/28

42/9 - 20/28 is 83/21.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 28 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 9 × 28 = 252,
42/9 = 42 × 28/9 × 28 = 1176/252
Likewise, for the 2nd fraction, since 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252
Subtract the two like fractions:
1176/252 - 180/252 = 1176 - 180/252 = 996/252
After reducing the fraction, the answer is 83/21
In mixed form: 320/21

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