Subtract 30/18 from 24/42, Solve 24/42

Subtract 30/18 from 24/42

1^st number: 24/42, 2^nd number: 1 12/18

24/42 - 30/18 is -23/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
24/42 = 24 × 3/42 × 3 = 72/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Subtract the two like fractions:
72/126 - 210/126 = 72 - 210/126 = -138/126
After reducing the fraction, the answer is -23/21

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