Subtract 1/42 from 98/20, Solve 4 18/20

Subtract 1/42 from 98/20

1^st number: 4 18/20, 2^nd number: 1/42

98/20 - 1/42 is 512/105.

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,
98/20 = 98 × 21/20 × 21 = 2058/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
1/42 = 1 × 10/42 × 10 = 10/420
Subtract the two like fractions:
2058/420 - 10/420 = 2058 - 10/420 = 2048/420
After reducing the fraction, the answer is 512/105
In mixed form: 492/105

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