The probability distribution of a random variable x is given below. x 1 2 5 8 9 p(x = x) 1⁄7 9⁄35 1⁄5 2⁄7 4⁄35 given the mean exam image find the variance (var(x)) and the standard deviation, respectively.\

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204

it's d

step-by-step explanation:

7

step-by-step explanation:

answer: a

step-by-step explanation: the answer is a due to the rule of symmetry; that a line of symmetry must divide a figure into 2 pieces that are the exact same, only reflected over a line of symmetry. b and c do not have lines of symmetry and would not divide the figure evenly, thus making the answer a.