Subtract 18/72 from 42/2, Solve 21 0/2

Subtract 18/72 from 42/2

1^st number: 21 0/2, 2^nd number: 18/72

42/2 - 18/72 is 83/4.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 2 × 36 = 72,
42/2 = 42 × 36/2 × 36 = 1512/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
18/72 = 18 × 1/72 × 1 = 18/72
Subtract the two like fractions:
1512/72 - 18/72 = 1512 - 18/72 = 1494/72
After reducing the fraction, the answer is 83/4
In mixed form: 203/4

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