Subtract 45/16 from 30/21, Solve 1 9/21

Subtract 45/16 from 30/21

1^st number: 1 9/21, 2^nd number: 2 13/16

30/21 - 45/16 is -155/112.

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

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 21 × 16 = 336,
30/21 = 30 × 16/21 × 16 = 480/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
45/16 = 45 × 21/16 × 21 = 945/336
Subtract the two like fractions:
480/336 - 945/336 = 480 - 945/336 = -465/336
After reducing the fraction, the answer is -155/112

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