Subtract 72/42 from 8/30, Solve 8/30

Subtract 72/42 from 8/30

1^st number: 8/30, 2^nd number: 1 30/42

8/30 - 72/42 is -152/105.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
8/30 = 8 × 7/30 × 7 = 56/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210
Subtract the two like fractions:
56/210 - 360/210 = 56 - 360/210 = -304/210
After reducing the fraction, the answer is -152/105

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