Subtract 90/70 from 1/63, Solve 1/63

Subtract 90/70 from 1/63

1^st number: 1/63, 2^nd number: 1 20/70

1/63 - 90/70 is -80/63.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 63 × 10 = 630,
1/63 = 1 × 10/63 × 10 = 10/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Subtract the two like fractions:
10/630 - 810/630 = 10 - 810/630 = -800/630
After reducing the fraction, the answer is -80/63

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