Subtract 15/45 from 30/7, Solve 4 2/7

Subtract 15/45 from 30/7

1^st number: 4 2/7, 2^nd number: 15/45

30/7 - 15/45 is 83/21.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 7 × 45 = 315,
30/7 = 30 × 45/7 × 45 = 1350/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
15/45 = 15 × 7/45 × 7 = 105/315
Subtract the two like fractions:
1350/315 - 105/315 = 1350 - 105/315 = 1245/315
After reducing the fraction, the answer is 83/21
In mixed form: 320/21

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