Subtract 6/9 from 90/70, Solve 1 20/70

Subtract 6/9 from 90/70

1^st number: 1 20/70, 2^nd number: 6/9

90/70 - 6/9 is 13/21.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Likewise, for the 2nd fraction, since 9 × 70 = 630,
6/9 = 6 × 70/9 × 70 = 420/630
Subtract the two like fractions:
810/630 - 420/630 = 810 - 420/630 = 390/630
After reducing the fraction, the answer is 13/21

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