Subtract 70/42 from 2/90, Solve 2/90

Subtract 70/42 from 2/90

1^st number: 2/90, 2^nd number: 1 28/42

2/90 - 70/42 is -74/45.

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,
2/90 = 2 × 7/90 × 7 = 14/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
70/42 = 70 × 15/42 × 15 = 1050/630
Subtract the two like fractions:
14/630 - 1050/630 = 14 - 1050/630 = -1036/630
After reducing the fraction, the answer is -74/45

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