Subtract 80/70 from 30/18, Solve 1 12/18

Subtract 80/70 from 30/18

1^st number: 1 12/18, 2^nd number: 1 10/70

30/18 - 80/70 is 11/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 18 × 35 = 630,
30/18 = 30 × 35/18 × 35 = 1050/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
80/70 = 80 × 9/70 × 9 = 720/630
Subtract the two like fractions:
1050/630 - 720/630 = 1050 - 720/630 = 330/630
After reducing the fraction, the answer is 11/21

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