I finally received SSH after many suggestions. I am working with "Expectation" as applied to pot odds on pg. 28. I get all the prior examples from the book but I do not get this one (and later examples). Here is the example:

5c4c JhTd6c2s
Gut Shot Straight Draw requiring one of 4 treys. 4 outs.
4/46 = 11.5 - 1 = 10.5:1
I get that.

SSH says,"If we ignore the last betting round, you must have pot odds of 42 to 4 or 10.5 to 1 for your call to break even." This seems to just restate the information from the "outs" analysis?

The following is given for expectation:
0=(4)(10.5) + (42)(-1) = 42 - 42

Does the (4) and (42) come from the 42:4 odds?

Where does the (10.5) come from? If its from the 42:4 odds why is it restated in the same equation? It seems that the weights of 4 and 42 already take care of this ratio.

Where does (-1) come from? I get that it is money lost, but where does the value it come from (could it be 2 in some cases). Is it from the 1 in 10.5:1?

Thanks in advance.

(4) and (42) are the number of cards that are outs, and the number of cards that are not outs, respectively.

(10.5) is the required pot odds to make the call EV neutral.

(-1) is the size of the bet (negative because you lose).