Subtract 25/9 from 30/70, Solve 30/70

Subtract 25/9 from 30/70

1^st number: 30/70, 2^nd number: 2 7/9

30/70 - 25/9 is -148/63.

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,
30/70 = 30 × 9/70 × 9 = 270/630
Likewise, for the 2nd fraction, since 9 × 70 = 630,
25/9 = 25 × 70/9 × 70 = 1750/630
Subtract the two like fractions:
270/630 - 1750/630 = 270 - 1750/630 = -1480/630
After reducing the fraction, the answer is -148/63

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