Subtract 75/70 from 15/18, Solve 15/18

Subtract 75/70 from 15/18

1^st number: 15/18, 2^nd number: 1 5/70

15/18 - 75/70 is -5/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 18 × 35 = 630,
15/18 = 15 × 35/18 × 35 = 525/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
75/70 = 75 × 9/70 × 9 = 675/630
Subtract the two like fractions:
525/630 - 675/630 = 525 - 675/630 = -150/630
After reducing the fraction, the answer is -5/21

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