Step-by-step explanation:
-(-3x-5)=7x
3x+5=7x
4x=5
x=5/4
Answer:
1000 in
Step-by-step explanation:
Given
The dimension of the small cube is 1\ in.1 in.
No of the cubes is 10^6106
If the small cubes are arranged on the floor
The area of the cubes is
\Rightarrow 10^6\times 1^2\ in.^2⇒106×12 in.2
We are looking for the probability :

Transform the law to standard normal like this:

The above formula is equivalent to this one:

From normal law table, we read the value of

.

Solving the above equation for the score n:


, it is the score we are looking for.
Answer: 2.77
The expected value is positive, so you expect to gain on average $2.77 per draw.
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Explanation:
Define two events
W = winning = getting a card 4 or less
L = losing = getting 5 or higher
P(W) = probability of winning
P(W) = 12/52 since there are 12 cards that are four or less out of 52
P(W) = 3/13 for any suit of 13, there are 3 cards that are four or less
P(L) = 1-P(W)
P(L) = 1-3/13
P(L) = 13/13 - 3/13
P(L) = 10/13
V(W) = net value of winning
V(W) = 162
V(L) = net value of losing
V(L) = -45
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E(X) = expected value
E(X) = P(W)*V(W) + P(L)*V(L)
E(X) = (3/13)*162 + (10/13)*(-45)
E(X) = 36/13
E(X) = 2.76923076923077
E(X) = 2.77 rounding to two decimal places (to the nearest cent)
This game is in favor to the player since we got a positive expected value. A fair game would occur if the expected value was 0.