Sunday, January 3, 2010
Question 2: Dave's Puppy
Dave's new puppy is attached to a pole in the backyard with a ten foot leash. The puppy has ruined all of the grass within its reach and now the grass needs to be replaced. One package of grass seeds covers 20 squared feet and costs $3.50. How much will it cost Dave to reseed the grass?
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since the dog doesnt have to eat in a circle, it could have eaten the shape of a square. Each side would be 10 ft long because the leash can only go 10 ft! 10 ft times 10 ft = 100 ft total
ReplyDelete100 ft/20 ft per package = 5 packages. $3.50 times 5 = $17.50 Dave will have to spend a totl of $17.50 to accommodate the 100 ft of grass missing! there's one lesson here: don't leave yur dog on a 10 ft leash!
Iris
if the dog eats to the full extent of the boundary then the circle will have a radius of ten. Area = pi times (radius sqaured.) So 10 times 10 = 100 and pi is roughly 3.14 so 3.14 times 100=314. So 16 packages. 16 times $3.50 = $56.
ReplyDeleteHey everyone,
ReplyDeleteOk so my answer works provided that the dog was in the middle of the yard, and he eats in the circle. And I thought about Iris's idea, eating in a square but why wouldn't the dog eat every inch that he could? Anyway, So I did it that he ate in a circle. I don't know how to find the area of a circle so I drew a square around the circle. So each side is 20 ft so 20 times 20= 400. So the dog destroyed approximately 400 squared feet.400 divided by 20 is 20. So i times 3.50 by 20, which equaled $70.00. That's a lot of money to spent on grass! And I agree with Iris about the point about the leash.... see you later!
*Katty*
The answer is $56 of grass seed. I found this by first figuring out how many square feet of grass the dog wrecked.
ReplyDeleteI found the area by using the formula for the area of a circle A=πr^2. The radius is 10 feet. So the area equals 22/7 x 10 x10 = 314.28571sq ft.
The cost of the seed per square foot is $3.50/20 square feet = $.017 per square foot.
Next I figured out how many packages of seed are needed. 314.28570/20 = 15.714285 packages, so I must buy 16 packages.
16x$3.50=$56. That is how I found the answer for the total cost.
HI GUYS,
ReplyDeleteWOW QUINN I DID NOT JUST GET A SINGLE THING YOU SAID! But if u meant the radius times itself multiplied by pi yes i do get that.
I think Katty is correct on the circle thing (especially if the owners are starving the poor dog). The radius is 10 all around. So, 10 (aaaaaaaaaaaaaaaaaah wheres the times button) times 10 is 100. Times pi, which is 3.14 (i think, well thats what theyve told me) is um ya who cares just move the decimal over (2 spaces on the 3.14 because there is 2 0's on the 100) and you get your answer! In this case (according to my calculation things) is 314 squared feet. If you need 1 packed for 20 feet, then you would need 16 packs and have some left over. Then, you multiply 16 times 3.50$ wait im gonna do the calculations... is 56.00$. I think I did it the same way as Quinn (well i got the same answer) but in using words i understood more.
Ya so my final answer is 56.00$.
PS wow if my dog ate that much id be really mad!
Bi guys,
OH and the exact same way as Leo.
ReplyDeleteI did it the same way as most people. But anyways, I think that the dog ate in a circle. Therefore, since the area of a circle = π x r squared, the actual calculations are π multiplied 10 to the power of 2 or 100π ft squared in terms of pi or 314.16 ft squared. Since one package of seeds cover 20 ft squared, the number of packages required is 314 ÷ 20 which is 15.7. Then you round the packages to 16, 16 x $3.50 or $56.00.
ReplyDeletePI is 3.1415926535897932384626443383279...... weel those are the only ones i know, so yeah like most of the others i will multiply 10 (The radius) by itself which equals 100 times PI. so yeah it is...................................... its sort of simple just move hte decimal .... uhhhhh 2 places tot he right and yeah which means it is 314.1592653589793238462643383279 feet. and that number divided by 20 equals................this is hard..................... i cannot figure it out so i use google calculator and got 15.7079633........ so 15.7079633 x $3.50 equals..................................................54.9778715........ and yeah so hell pay approximately $54.98 cents.
ReplyDeletefirst of all i wanna say pie sucks unless it is eatable and second of all if this hungry dogg that i nicknamed chubbz actually eats a full circle and the radius is 10 and pie ( mmmmmm pie oh wait i gotta stay on track!) anyways the basic pie formula (mmmm) is 3.14 so u do 3.14 x radius which is 10cm2 and get 314 so rounding it up to 16 becuz 15.7 is stupid u get 16 bags and each bag costs more than a pack of bubble gum ( oh wait ummm ) sorrry each one costs $3.50 so 16 bags x 3.50 is more than a pack of bubblegum! anyways 3.50x16 is $56.00 which is equal to 36.782354747583573o5375835732520201364936 packs of bubble gum! so the answer is $56 dollars ( not squared) by THE MIGHTY GONTHORIAN
ReplyDeleteOk so i'm a little late on this one but anyway, the answer is that Dave had to spend $56 to buy 16 bags of grass seed for 314cm2. I got that by using the area formula of area = πr2, that is 3.14x10x10 because lets face it people the puppy would eat every inch he could get so you have a circle problem here.
ReplyDelete