Subtract 5/42 from 84/20, Solve 4 4/20

Subtract 5/42 from 84/20

1^st number: 4 4/20, 2^nd number: 5/42

84/20 - 5/42 is 857/210.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
84/20 = 84 × 21/20 × 21 = 1764/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
5/42 = 5 × 10/42 × 10 = 50/420
Subtract the two like fractions:
1764/420 - 50/420 = 1764 - 50/420 = 1714/420
After reducing the fraction, the answer is 857/210
In mixed form: 417/210

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