Subtract 45/7 from 54/15, Solve 3 9/15

Subtract 45/7 from 54/15

1^st number: 3 9/15, 2^nd number: 6 3/7

54/15 - 45/7 is -99/35.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
54/15 = 54 × 7/15 × 7 = 378/105
Likewise, for the 2nd fraction, since 7 × 15 = 105,
45/7 = 45 × 15/7 × 15 = 675/105
Subtract the two like fractions:
378/105 - 675/105 = 378 - 675/105 = -297/105
After reducing the fraction, the answer is -99/35

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