Subtract 20/42 from 84/3, Solve 28 0/3

Subtract 20/42 from 84/3

1^st number: 28 0/3, 2^nd number: 20/42

84/3 - 20/42 is 578/21.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 3 × 14 = 42,
84/3 = 84 × 14/3 × 14 = 1176/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
20/42 = 20 × 1/42 × 1 = 20/42
Subtract the two like fractions:
1176/42 - 20/42 = 1176 - 20/42 = 1156/42
After reducing the fraction, the answer is 578/21
In mixed form: 2711/21

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