Subtract 30/45 from 50/21, Solve 2 8/21

Subtract 30/45 from 50/21

1^st number: 2 8/21, 2^nd number: 30/45

50/21 - 30/45 is 12/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
50/21 = 50 × 15/21 × 15 = 750/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
30/45 = 30 × 7/45 × 7 = 210/315
Subtract the two like fractions:
750/315 - 210/315 = 750 - 210/315 = 540/315
After reducing the fraction, the answer is 12/7
In mixed form: 15/7

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