Subtract 45/5 from 63/21, Solve 3 0/21

Subtract 45/5 from 63/21

1^st number: 3 0/21, 2^nd number: 9 0/5

63/21 - 45/5 is -6/1.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
63/21 = 63 × 5/21 × 5 = 315/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
45/5 = 45 × 21/5 × 21 = 945/105
Subtract the two like fractions:
315/105 - 945/105 = 315 - 945/105 = -630/105
After reducing the fraction, the answer is -6/1

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