Subtract 21/16 from 21/45, Solve 21/45

Subtract 21/16 from 21/45

1^st number: 21/45, 2^nd number: 1 5/16

21/45 - 21/16 is -203/240.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 16 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720
Likewise, for the 2nd fraction, since 16 × 45 = 720,
21/16 = 21 × 45/16 × 45 = 945/720
Subtract the two like fractions:
336/720 - 945/720 = 336 - 945/720 = -609/720
After reducing the fraction, the answer is -203/240

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