Assuming that 10% is the probability of a switch being defective (since left-handedness has nothing to do with the problem):
For a binomial distribution, probability(r out of n) = (nCr) (p)^r (q)^(1-r)
p = 10% = 0.1, q = 1 - p = 0.9
r = 2 switches, n = total of 12 switches
probability = (12C2) (0.1)^2 (0.9)^(12-2)
probability = 66(0.1)^2 (0.9)^10
probability = 0.23
The volume:
Pi x r^2 x h
V = pi x 12^2 x 7
V = 1008pi units^3
The answer would be a
hope it helps.
The answer would be A. When using Cramer's Rule to solve a system of equations, if the determinant of the coefficient matrix equals zero and neither numerator determinant is zero, then the system has infinite solutions. It would be hard finding this answer when we use the Cramer's Rule so instead we use the Gauss Elimination. Considering the equations:
x + y = 3 and <span>2x + 2y = 6
Determinant of the equations are </span>
<span>| 1 1 | </span>
<span>| 2 2 | = 0
</span>
the numerator determinants would be
<span>| 3 1 | . .| 1 3 | </span>
<span>| 6 2 | = | 2 6 | = 0.
Executing Gauss Elimination, any two numbers, whose sum is 3, would satisfy the given system. F</span>or instance (3, 0), <span>(2, 1) and (4, -1). Therefore, it would have infinitely many solutions. </span>
1. I think this one is 1/3
2. 38 feet
