Monday

March 30, 2015

March 30, 2015

Posted by **ann** on Friday, April 13, 2012 at 11:40pm.

ballfield costs 14,850,00 to build. the cost per city resident to build it will be based on last census. New census shows population increased by 2200 people, which reduced the cost per resident $75. what is the current population of the city?? thank you

- algebra -
**Reiny**, Friday, April 13, 2012 at 11:57pmThe way you grouped the cost by thousands, I think you left out a zero

is it 14 850 000 ?

let currect population be x

last year's population is x - 2200

currect cost per person = 14850000/x

last year's cost per person = 14850000/(x-2200)

14850000/(x-2200) - 14850000/x = 75

14850000x - 14850000(x-2) = 75x(x-2200)

75x^2 - 165000x - 14850000(2200) = 0

x^2 - 2200x = 435 600 000

x^2 - 2200x + 1210000 = 435 600 000 + 1 210 000

(x - 1100)^2 = 436 810 000

x - 1100 = 20900

x = 22 000

check:

current pop: = 22000

cost per person = 14850000/22000 = 675

last years' pop = 19800

cost per person = 14850000/19800 = 750

change = 750-675 = 75 , YEAHH!

- algebra -
**ann**, Saturday, April 14, 2012 at 1:02amyes you were right about the zero. Thank you so much for showing me how to do it. ann

**Answer this Question**

**Related Questions**

Math (algebra) - I have no idea how to solve this problem... A village wants to ...

Algebra 1- 8th Grade - According to the 1990 Census, the population of the ...

math - The2010 census shows that the population of New Jersey increased by 4.5...

History - With over eight million people, New York City is the most heavily ...

Math - According to the U. S. Census Bureau, the total 2008 U.S. population was ...

Algebra 2 - According to the US Census Bureau, the population of the United ...

Math Help - 8. One nanometer is about 0.00000003937 of an inch. What is this ...

Math - A census-taker rings Mr. Manning's bell and asks how many children he has...

Grade 8 Math PLZ PPL help its hard - A census-taker rings Mr. Manning's bell ...

Algebra - Aki's Bicycle designs has determined that when x hundred bicyles are ...