Subtract 20/84 from 42/5, Solve 8 2/5

Subtract 20/84 from 42/5

1^st number: 8 2/5, 2^nd number: 20/84

42/5 - 20/84 is 857/105.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 5 × 84 = 420,
42/5 = 42 × 84/5 × 84 = 3528/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
20/84 = 20 × 5/84 × 5 = 100/420
Subtract the two like fractions:
3528/420 - 100/420 = 3528 - 100/420 = 3428/420
After reducing the fraction, the answer is 857/105
In mixed form: 817/105

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