Subtract 80/24 from 9/21, Solve 9/21

Subtract 80/24 from 9/21

1^st number: 9/21, 2^nd number: 3 8/24

9/21 - 80/24 is -61/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
9/21 = 9 × 8/21 × 8 = 72/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
80/24 = 80 × 7/24 × 7 = 560/168
Subtract the two like fractions:
72/168 - 560/168 = 72 - 560/168 = -488/168
After reducing the fraction, the answer is -61/21

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