Subtract 60/12 from 21/45, Solve 21/45

Subtract 60/12 from 21/45

1^st number: 21/45, 2^nd number: 5 0/12

21/45 - 60/12 is -68/15.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 12 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
60/12 = 60 × 15/12 × 15 = 900/180
Subtract the two like fractions:
84/180 - 900/180 = 84 - 900/180 = -816/180
After reducing the fraction, the answer is -68/15

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