Subtract 27/8 from 20/45, Solve 20/45

Subtract 27/8 from 20/45

1^st number: 20/45, 2^nd number: 3 3/8

20/45 - 27/8 is -211/72.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 8 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 45 × 8 = 360,
20/45 = 20 × 8/45 × 8 = 160/360
Likewise, for the 2nd fraction, since 8 × 45 = 360,
27/8 = 27 × 45/8 × 45 = 1215/360
Subtract the two like fractions:
160/360 - 1215/360 = 160 - 1215/360 = -1055/360
After reducing the fraction, the answer is -211/72

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