[jodo10]

If an underdog has a 45% probability of winning the game outright, what is the probability that the underdog covers the spread ? In this example, assume the spread is +3.5. Thank you, in advance.

[xyz]

You need to know the total to do this calculation.

[LT Profits]

And the sport would help too.

[Cookie Monster]

With the data you provided, the only possible answer is:
45% + prob the dog losses 1, 2 or 3

[jodo10]

XYZ: The total is 198.

LT Profits: The sport is NBA.

Cookie Monster: Thank you. That is the general set up I had in mind but I got stuck there. Any tips?

[jodo10]

XYZ: The total is 198 and the sport is NBA.

[jodo10]

Thank you.

[Cookie Monster]

The lazy way:
Use the SBR half point calculator
Enter NBA / Spread / 0 -122.2/+122.2 (from 55/45)
Click in the down arrow looking for -3
The no vig is +114.3/-114.3, with a 3.83% push rate
It means 53.3% of winning, but adjusting for push, 51.3% win, 3.83% push, 44.9% loss
It is not the most exact number, but should be close.
You can use it for every sport.
You are welcome.

I recommend you not use the Think Thank forum for asking basic questions. This forum has less traffic, and posters usually search for advanced topics or discuss ideas.

[LT Profits]

The lazy way:
Use the SBR half point calculator
Enter NBA / Spread / 0 -122.2/+122.2 (from 55/45)
Click in the down arrow looking for -3
The no vig is +114.3/-114.3, with a 3.83% push rate
It means 53.3% of winning, but adjusting for push, 51.3% win, 3.83% push, 44.9% loss
It is not the most exact number, but should be close.
You can use it for every sport.
You are welcome.

I recommend you not use the Think Thank forum for asking basic questions. This forum has less traffic, and posters usually search for advanced topics or discuss ideas.

Close but flawed because the Calculator does not consider totals. Although the total of this game is basically on this year's league average of 198.6, so calculator could work this time.