Subtract 30/7 from 45/18, Solve 2 9/18

Subtract 30/7 from 45/18

1^st number: 2 9/18, 2^nd number: 4 2/7

45/18 - 30/7 is -25/14.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
45/18 = 45 × 7/18 × 7 = 315/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
30/7 = 30 × 18/7 × 18 = 540/126
Subtract the two like fractions:
315/126 - 540/126 = 315 - 540/126 = -225/126
After reducing the fraction, the answer is -25/14

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