Subtract 90/21 from 54/16, Solve 3 6/16

Subtract 90/21 from 54/16

1^st number: 3 6/16, 2^nd number: 4 6/21

54/16 - 90/21 is -51/56.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 21 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 16 × 21 = 336,
54/16 = 54 × 21/16 × 21 = 1134/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
90/21 = 90 × 16/21 × 16 = 1440/336
Subtract the two like fractions:
1134/336 - 1440/336 = 1134 - 1440/336 = -306/336
After reducing the fraction, the answer is -51/56

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