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

Subtract 18/80 from 42/10

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

42/10 - 18/80 is 159/40.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 10 × 8 = 80,
42/10 = 42 × 8/10 × 8 = 336/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
18/80 = 18 × 1/80 × 1 = 18/80
Subtract the two like fractions:
336/80 - 18/80 = 336 - 18/80 = 318/80
After reducing the fraction, the answer is 159/40
In mixed form: 339/40

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