Subtract 80/45 from 21/16, Solve 1 5/16

Subtract 80/45 from 21/16

1^st number: 1 5/16, 2^nd number: 1 35/45

21/16 - 80/45 is -67/144.

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

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 16 × 45 = 720,
21/16 = 21 × 45/16 × 45 = 945/720
Likewise, for the 2nd fraction, since 45 × 16 = 720,
80/45 = 80 × 16/45 × 16 = 1280/720
Subtract the two like fractions:
945/720 - 1280/720 = 945 - 1280/720 = -335/720
After reducing the fraction, the answer is -67/144

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