Subtract 30/42 from 84/20, Solve 4 4/20

Subtract 30/42 from 84/20

1^st number: 4 4/20, 2^nd number: 30/42

84/20 - 30/42 is 122/35.

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,
30/42 = 30 × 10/42 × 10 = 300/420
Subtract the two like fractions:
1764/420 - 300/420 = 1764 - 300/420 = 1464/420
After reducing the fraction, the answer is 122/35
In mixed form: 317/35

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