Subtract 18/80 from 42/4, Solve 10 2/4

Subtract 18/80 from 42/4

1^st number: 10 2/4, 2^nd number: 18/80

42/4 - 18/80 is 411/40.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 4 × 20 = 80,
42/4 = 42 × 20/4 × 20 = 840/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
18/80 = 18 × 1/80 × 1 = 18/80
Subtract the two like fractions:
840/80 - 18/80 = 840 - 18/80 = 822/80
After reducing the fraction, the answer is 411/40
In mixed form: 1011/40

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