Subtract 42/9 from 45/70, Solve 45/70

Subtract 42/9 from 45/70

1^st number: 45/70, 2^nd number: 4 6/9

45/70 - 42/9 is -169/42.

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,
45/70 = 45 × 9/70 × 9 = 405/630
Likewise, for the 2nd fraction, since 9 × 70 = 630,
42/9 = 42 × 70/9 × 70 = 2940/630
Subtract the two like fractions:
405/630 - 2940/630 = 405 - 2940/630 = -2535/630
After reducing the fraction, the answer is -169/42

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