Subtract 4/90 from 50/21, Solve 2 8/21

Subtract 4/90 from 50/21

1^st number: 2 8/21, 2^nd number: 4/90

50/21 - 4/90 is 736/315.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
50/21 = 50 × 30/21 × 30 = 1500/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
4/90 = 4 × 7/90 × 7 = 28/630
Subtract the two like fractions:
1500/630 - 28/630 = 1500 - 28/630 = 1472/630
After reducing the fraction, the answer is 736/315
In mixed form: 2106/315

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