Subtract 15/9 from 7/42, Solve 7/42

Subtract 15/9 from 7/42

1^st number: 7/42, 2^nd number: 1 6/9

7/42 - 15/9 is -3/2.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
7/42 = 7 × 3/42 × 3 = 21/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
15/9 = 15 × 14/9 × 14 = 210/126
Subtract the two like fractions:
21/126 - 210/126 = 21 - 210/126 = -189/126
After reducing the fraction, the answer is -3/2

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