Subtract 50/21 from 9/18, Solve 9/18

Subtract 50/21 from 9/18

1^st number: 9/18, 2^nd number: 2 8/21

9/18 - 50/21 is -79/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
9/18 = 9 × 7/18 × 7 = 63/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
50/21 = 50 × 6/21 × 6 = 300/126
Subtract the two like fractions:
63/126 - 300/126 = 63 - 300/126 = -237/126
After reducing the fraction, the answer is -79/42

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