Statistics

1. (.012x - .17)(.3x + .54)

(0.012x) (0.3x) + (0.012x) (0.54) – (0.17) (0.3x) – (0.17) (0.54)

0.0036x2+ 0.00648x-0.051x

0.0036x2-0.0445x-0.0918

2. A well known golfer sells his book help for hackers for $13.25 per copy. His fixed costs are $125,000 and he estimates that the variable cost of printing, binding, and distribution are given by -4x2+ 2880x – 295 dollars. Find expressions for the revenue, cost and profit from selling x thousand copies of the book.

Revenue= (price per item) * (number of items sold)

= 13.25*1000x = 13250x

Cost = fixed costs + variable costs

125000+ -4x2+2880x-295

125000-4x2+2880x-295

Profit = Revenue – cost

13250x – (125000-4x2+2880x-295)

13250x-125000+4x2 -2880x +295

P = 4x2 +10370x-124705

3. r2+16r +60 (factor the polynomial)

(r+10) (r+6)

r= 6, 10.

4. 10x2 – 17x + 3 (factor each polynomial completely. Factor out the greatest common factor as necessary)

3+ -17x + 10x2 = 0

3 + -17x + 10x2 = 0

(1 + -5x)(3 + -2x) = 0

1 + -5x = 0

1 + -1 + -5x = 0 + -1

0 + -5x = 0 + -1

-5x = 0 + -1

-5x = -1

x = 0.2

3 + -2x = 0

3 + -2x = 0

3 + -3 + -2x = 0 + -3

0 + -2x = 0 + -3

-2x = 0 + -3

-2x = -3

x = 1.5

x = {0.2, 1.5}

3 2k+86 / 3k+123

2(k+4)6*33(k+4) = 13

4 12r+2436r-36 / 6r+128r-8

12(r+2)36(r-1)* 8(r-1)6(r+2) 49

5 When a loan is paid off early, a portion of the finance charge must be returned to the borrower. By one method of calculating the finance charge, the amount of unearned interest (finance charge to be returned) is given by...