CPhill

log P   =  - kd

log P   = - 20 (0.005)

Log P  = -0.1

This says that P   =  

10^(-0.1)  = about  0.794   = about 79.4%

S =  pi * r * (given degrees/ 180)   .....where S is the arc length

So

r =   [ S * 180 ]  / [ pi * given degrees]

I don't know what you mean by "equivalent".....but we can solve this

4(x-2)<7x+1      simplify

4x - 8 < 7x + 1       add 8 to both sides and subtract 7x from both sides

-3x < 9                  divide both sides by -3 and reverse the inequality sign

x  >  -3

By factoring

x^2 + 2x + 1   = 0     can be factored as

(x + 1) (x + 1)  = 0

And setting either factor to 0  and solving, we have that 

x + 1 = 0      subtract 1 from both sides

x = -1

I'm not sure as to what you're calculating, but,  if we're asking the probability of a 7  or the probability of a double, we have :

P ( 7 or a double)  =  P(7)  + P(double)  - P(7 and a double)

The last term is 0.......no doubles  equal 7

P(7)   .......there are 36 possibilities when we roll 2 dice........the probability of a 7  =  6/36    ....and the probabilty of a double =  6/36

So

P(7 or a double)  = 6/36   + 6/36  -  0      =   12/36  =  1/3

30 * 10  = 300

1. The probability that she wins the first 3 games and loses the last 2 is:

.(.82)(.82)(.82)(.18)(.18)= about 1.786%

2. The probability that she will win at least 1 game  = 1 - probability that she doesn't win any games =

1 - (.18)^5  =  > 99%

5(3)  - 7    =   15 - 7   = 8

Next to the "2nd" button at the top left of the calculator

See my answer here, Kawaii   ...    http://web2.0calc.com/questions/how-am-i-gonna-express-the-ratio-in-lowest-terms-of-consonants-to-vowels-in-each-name