Subtract 21/42 from 24/18, Solve 1 6/18

Subtract 21/42 from 24/18

1^st number: 1 6/18, 2^nd number: 21/42

24/18 - 21/42 is 5/6.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
24/18 = 24 × 7/18 × 7 = 168/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126
Subtract the two like fractions:
168/126 - 63/126 = 168 - 63/126 = 105/126
After reducing the fraction, the answer is 5/6

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