Subtract 80/42 from 30/9, Solve 3 3/9

Subtract 80/42 from 30/9

1^st number: 3 3/9, 2^nd number: 1 38/42

30/9 - 80/42 is 10/7.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 42 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 9 × 14 = 126,
30/9 = 30 × 14/9 × 14 = 420/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
80/42 = 80 × 3/42 × 3 = 240/126
Subtract the two like fractions:
420/126 - 240/126 = 420 - 240/126 = 180/126
After reducing the fraction, the answer is 10/7
In mixed form: 13/7

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