Subtract 21/9 from 28/42, Solve 28/42

Subtract 21/9 from 28/42

1^st number: 28/42, 2^nd number: 2 3/9

28/42 - 21/9 is -5/3.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
28/42 = 28 × 3/42 × 3 = 84/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
21/9 = 21 × 14/9 × 14 = 294/126
Subtract the two like fractions:
84/126 - 294/126 = 84 - 294/126 = -210/126
After reducing the fraction, the answer is -5/3

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