Subtract 27/21 from 30/10, Solve 3 0/10

Subtract 27/21 from 30/10

1^st number: 3 0/10, 2^nd number: 1 6/21

30/10 - 27/21 is 12/7.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
30/10 = 30 × 21/10 × 21 = 630/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
27/21 = 27 × 10/21 × 10 = 270/210
Subtract the two like fractions:
630/210 - 270/210 = 630 - 270/210 = 360/210
After reducing the fraction, the answer is 12/7
In mixed form: 15/7

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