Subtract 15/18 from 30/7, Solve 4 2/7

Subtract 15/18 from 30/7

1^st number: 4 2/7, 2^nd number: 15/18

30/7 - 15/18 is 145/42.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 7 × 18 = 126,
30/7 = 30 × 18/7 × 18 = 540/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126
Subtract the two like fractions:
540/126 - 105/126 = 540 - 105/126 = 435/126
After reducing the fraction, the answer is 145/42
In mixed form: 319/42

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