Same girl can be chosen for both jobs, is the probability with replacement. Multiply the individual probabilities.
(6/20) * (6/20) = 9/100
Answer:
B
Step-by-step explanation:
600+12000+12000+35000=59600
We are usually concerned with one reaction. That is, the production of one specific set of products from a specific set of reactants.
The number of values of c/d would be the number of possible ways that a and b could recombine to form different pairs of products c and d. (You might get different reactions at different temperatures, for example. Or, you might get different pars of ions.)
Usually, the number of values of c/d is one (1). (Of course, if you simply swap what you're calling "c" and "d", then you double that number, whatever it is.)
Answers:
Row 0: 1
Row 1: 1 1
Row 2: 1 2 1
Row 3: 1 3 3 1
Row 4: 1 4 6 4 1
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Explanation:
This is known as Pascal's Triangle. Each value, other than the '1's, is found by adding the values directly above it. For instance, the '4' is the result of 1+3, and the 6 is a result of 3+3, and so on.
You can use the nCr combination formula to find the same values.
Alternatively you can expand out binomials of the form (x+y)^n, for integer values of n, and you'll find the coefficients of the terms match perfectly with Pascal's Triangle.