Subtract 2/21 from 98/90, Solve 1 8/90

Subtract 2/21 from 98/90

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

98/90 - 2/21 is 313/315.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
98/90 = 98 × 7/90 × 7 = 686/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
2/21 = 2 × 30/21 × 30 = 60/630
Subtract the two like fractions:
686/630 - 60/630 = 686 - 60/630 = 626/630
After reducing the fraction, the answer is 313/315

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