Subtract 32/20 from 9/21, Solve 9/21

Subtract 32/20 from 9/21

1^st number: 9/21, 2^nd number: 1 12/20

9/21 - 32/20 is -41/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
9/21 = 9 × 20/21 × 20 = 180/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
32/20 = 32 × 21/20 × 21 = 672/420
Subtract the two like fractions:
180/420 - 672/420 = 180 - 672/420 = -492/420
After reducing the fraction, the answer is -41/35

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