Subtract 20/16 from 7/45, Solve 7/45

Subtract 20/16 from 7/45

1^st number: 7/45, 2^nd number: 1 4/16

7/45 - 20/16 is -197/180.

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,
7/45 = 7 × 16/45 × 16 = 112/720
Likewise, for the 2nd fraction, since 16 × 45 = 720,
20/16 = 20 × 45/16 × 45 = 900/720
Subtract the two like fractions:
112/720 - 900/720 = 112 - 900/720 = -788/720
After reducing the fraction, the answer is -197/180

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