Answers

Subtract 40/42 from 30/45

30/45 - 40/42 is -2/7.

Steps for subtracting fractions

1. 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
2. For the 1st fraction, since 45 × 14 = 630,
   30/45 = 30 × 14/45 × 14 = 420/630
3. Likewise, for the 2nd fraction, since 42 × 15 = 630,
   40/42 = 40 × 15/42 × 15 = 600/630
4. Subtract the two like fractions:
   420/630 - 600/630 = 420 - 600/630 = -180/630
5. After reducing the fraction, the answer is -2/7

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