Subtract 20/42 from 2/45, Solve 2/45

Subtract 20/42 from 2/45

2/45 - 20/42 is -136/315.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
2/45 = 2 × 14/45 × 14 = 28/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
20/42 = 20 × 15/42 × 15 = 300/630
Subtract the two like fractions:
28/630 - 300/630 = 28 - 300/630 = -272/630
After reducing the fraction, the answer is -136/315

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