Subtract 45/7 from 18/90, Solve 18/90

Subtract 45/7 from 18/90

1^st number: 18/90, 2^nd number: 6 3/7

18/90 - 45/7 is -218/35.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 7 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630
Likewise, for the 2nd fraction, since 7 × 90 = 630,
45/7 = 45 × 90/7 × 90 = 4050/630
Subtract the two like fractions:
126/630 - 4050/630 = 126 - 4050/630 = -3924/630
After reducing the fraction, the answer is -218/35

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