Subtract 45/42 from 36/90, Solve 36/90

Subtract 45/42 from 36/90

1^st number: 36/90, 2^nd number: 1 3/42

36/90 - 45/42 is -47/70.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
36/90 = 36 × 7/90 × 7 = 252/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
45/42 = 45 × 15/42 × 15 = 675/630
Subtract the two like fractions:
252/630 - 675/630 = 252 - 675/630 = -423/630
After reducing the fraction, the answer is -47/70

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