Subtract 80/8 from 21/45, Solve 21/45

Subtract 80/8 from 21/45

1^st number: 21/45, 2^nd number: 10 0/8

21/45 - 80/8 is -143/15.

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,
21/45 = 21 × 8/45 × 8 = 168/360
Likewise, for the 2nd fraction, since 8 × 45 = 360,
80/8 = 80 × 45/8 × 45 = 3600/360
Subtract the two like fractions:
168/360 - 3600/360 = 168 - 3600/360 = -3432/360
After reducing the fraction, the answer is -143/15

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