Subtract 21/42 from 49/9, Solve 5 4/9

Subtract 21/42 from 49/9

1^st number: 5 4/9, 2^nd number: 21/42

49/9 - 21/42 is 89/18.

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,
49/9 = 49 × 14/9 × 14 = 686/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126
Subtract the two like fractions:
686/126 - 63/126 = 686 - 63/126 = 623/126
After reducing the fraction, the answer is 89/18
In mixed form: 417/18

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