Subtract 8/90 from 25/21, Solve 1 4/21

Subtract 8/90 from 25/21

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

25/21 - 8/90 is 347/315.

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,
25/21 = 25 × 30/21 × 30 = 750/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
8/90 = 8 × 7/90 × 7 = 56/630
Subtract the two like fractions:
750/630 - 56/630 = 750 - 56/630 = 694/630
After reducing the fraction, the answer is 347/315
In mixed form: 132/315

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