Subtract 4/42 from 25/21, Solve 1 4/21

Subtract 4/42 from 25/21

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

25/21 - 4/42 is 23/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
25/21 = 25 × 2/21 × 2 = 50/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
4/42 = 4 × 1/42 × 1 = 4/42
Subtract the two like fractions:
50/42 - 4/42 = 50 - 4/42 = 46/42
After reducing the fraction, the answer is 23/21
In mixed form: 12/21

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