I have an Algebra question??

Question

I'm in 9th grade and my mom really doesnt know how to do math and my sister isnt here and i dont live with my dad so can someone help me with this question?...The amount of fertilizer needed for a lawn varies directly with the area of the lawn. If 4 pounds of fertilizer are needed for 500 square feet of lawn, how much is needed for Dr. Brown's lawn, which is rectangular in shape and measures 25 feet by 50 feet?..I'm pretty sure you set up a proportion but i'm not sure how you would set it up. If someone could just help me set it up I can find the answer. Thank you!

Answer 1

first find the area of Mr.brown's lawn by the equation A=lw
it will be A=25 x 50 = 1250 square feet.
Now,some fraction 4/500=x/1250 where x is your answer.
cross multiplication will give you x =10 pounds
so you need 10 pounds of fertilizer.

Answer 2

First, figure out the area of Doc's lawn:
50 X 25 = 1250
Then divide this by the area of the lawn for which you know the right amount of fertilizer:
1250/500 = 2.5
Then multiply this by the amount of fertilizer needed on the example lawn:
2.5 X 4 = 10 pounds

Answer 3

first find the area of Mr.brown's lawn by the equation A=lw
it will be A=25 x 50 = 1250 square feet.
Now,some fraction 4/500=x/1250 where x is your answer.
cross multiplication will give you x =10 pounds
so you need 10 pounds of fertilizer

Answer 4

area of Dr.Brown's lawn=50*25=1250sft
using the proportion as the variation is direct
4:500::x:1250
product of the means =product of the extremes
500x=1250*4
x=1250*4/500=10
so 10 pounds ishat youwill need

Answer 5

Doctor browns lawn is 25ft x 50ft = 1250sq. ft.

So his lawn is 1250/500 = 2.5 times bigger than 500 sq. ft. and so he needs 2.5 times more fertilizer.

4 x 2.5 = 10 pounds.

Answer 6

Im sorry im in ninth grade too...lol but ill try....lets see....It looks like the problem should look like this
(25x50) / 500 x 4 = pounds of fertilizer...Yup that should work...soo there ya have it!!!!lol