Subtract 15/30 from 90/7, Solve 12 6/7

Subtract 15/30 from 90/7

1^st number: 12 6/7, 2^nd number: 15/30

90/7 - 15/30 is 173/14.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 7 × 30 = 210,
90/7 = 90 × 30/7 × 30 = 2700/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210
Subtract the two like fractions:
2700/210 - 105/210 = 2700 - 105/210 = 2595/210
After reducing the fraction, the answer is 173/14
In mixed form: 125/14

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