Subtract 90/21 from 81/32, Solve 2 17/32

Subtract 90/21 from 81/32

1^st number: 2 17/32, 2^nd number: 4 6/21

81/32 - 90/21 is -393/224.

Find the least common denominator or LCM of the two denominators:
LCM of 32 and 21 is 672

Next, find the equivalent fraction of both fractional numbers with denominator 672
For the 1st fraction, since 32 × 21 = 672,
81/32 = 81 × 21/32 × 21 = 1701/672
Likewise, for the 2nd fraction, since 21 × 32 = 672,
90/21 = 90 × 32/21 × 32 = 2880/672
Subtract the two like fractions:
1701/672 - 2880/672 = 1701 - 2880/672 = -1179/672
After reducing the fraction, the answer is -393/224

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