Math Story Problem - Superbowl queston?

Question

The probability that San Francisco plays in the next Super Bowl is nine times the probability that they do not play in the next Superbowl. The probability that SF plays in the next Superbowl plus the probability that they do not play is 1. What is the probability that SF plays in the next Superbowl. I know I have to set up two different equations, but how?

Answer 1

They do play = x
They don't = y

x+y = 1
x=9y

now replace x in the first equation
9y+y = 1

10y = 1

y = .1 = 10%

now since x+y = 1

x + .1 = 1

x = .9 = 90%

San Francisco supposedly has a 90% chance, which is definitely not true... GO BEARZ!

Answer 2

let a be the probability that San Francisco plays in the next Super Bowl
let b be the probability that they do not play in the next Superbowl
=> a=9b
The probability that SF plays in the next Superbowl plus the probability that they do not play is 1
a+b =1
=> a= 10% or 1/10
b=90% or 9/10
hope it's correct

Answer 3

You are correct that you need two eqns
So first you want to set up the variables so lets make SF in the Super Bowl = S and not in the Super Bowl = N

the first statement should look like this
9N = S

and the second should be
S + N = 1

So substitute S into the second eqn and you get
9N + N = 1 this is the same as

10N =1 and therefore N = 1/10

now put this into one of the two eqns I choose eqn 1 so we have now
9(1/10) = S therefore S = 9/10

hope this helps

Answer 4

"The probability that SF plays in the next Superbowl plus the probability that they do not play is 1."
This is true for all probabilities. The probability something will + won't = 1...

1 = x+9x
1=10x
x=.1
x = won't play = .1 therefor probability will = .9 or 90%

Answer 5

I will use W as the probability they play, and L as the probability they won't. Since the problem says the probability of playing is nine times as likely as not playing, the first equation will be:

W=9*L

It also says the two probabilities added up equals 1 so:

W+L=1

You should be able to find the exact numbers now by substitution.

Answer 6

Well basically. SF was a 10% chance of getting to a superbowl the next ten years.

Answer 7

OK.

say prob. that SA wins = W
and say prob. that SA loses = L

then..

W = 9 * L
W + L = 1 ( or L = 1- W)

(these are the 2 equations)

there fore..

W = 9 * (1- W)
W = 9 - 9W
10 W = 9
and W = 9/10
W = 0.9

Which means L = 0.1

(W + L = 0.9 + 0.1 = 1)

Hope this helps....

Good Luck..

Answer 8

Theoretically 0. wearing in basic terms one thousand at a time and eating a million in line with mile for one thousand miles could effect in there being 0 bananas left whilst Corey arrived on the marketplace. besides, Corey could no longer stroll lower back because of the fact there are not any bananas left for the holiday.

Answer 9

so they are nine times more likely to go on then not. Nine chances to go and 1 to not. They have a 90% chance of going on and a 10% of not, i think

Answer 10

Let P( do not play) = x
Then P(play) = 9*x
And P(play) + P(do not play) = 9x + x = 10x = 1
So x = 1/10 = 0.1 = P(do not play)
And 9 * 0.1 = 0.9 = P(play)

hope that helps!