Subtract 25/21 from 18/4, Solve 4 2/4

Subtract 25/21 from 18/4

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

18/4 - 25/21 is 139/42.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
18/4 = 18 × 21/4 × 21 = 378/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
25/21 = 25 × 4/21 × 4 = 100/84
Subtract the two like fractions:
378/84 - 100/84 = 378 - 100/84 = 278/84
After reducing the fraction, the answer is 139/42
In mixed form: 313/42

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