The first 4 terms of a 10-term geometric series are listed below. Which expression represents the sum of the series?
+ 4 + 10 + ... +010
16
16
25
25

answer: 48

just remember to use pemdas:

parentheses

expressions

multiplication

division

addition

subtraction

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

make sure you have version 2.50

try looking in the very back of the book : )

step-by-step explanation:

you can download it here