Subtract 80/90 from 25/21, Solve 1 4/21

Subtract 80/90 from 25/21

1^st number: 1 4/21, 2^nd number: 80/90

25/21 - 80/90 is 19/63.

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,
80/90 = 80 × 7/90 × 7 = 560/630
Subtract the two like fractions:
750/630 - 560/630 = 750 - 560/630 = 190/630
After reducing the fraction, the answer is 19/63

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