Subtract 42/80 from 30/10, Solve 3 0/10

Subtract 42/80 from 30/10

1^st number: 3 0/10, 2^nd number: 42/80

30/10 - 42/80 is 99/40.

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,
30/10 = 30 × 8/10 × 8 = 240/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80
Subtract the two like fractions:
240/80 - 42/80 = 240 - 42/80 = 198/80
After reducing the fraction, the answer is 99/40
In mixed form: 219/40

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