## anonymous 4 years ago a painter is hired to paint a silo that had the dimmensions shown below. one gallon of paintcovers 400 square feet. how many gallons of paint does the painter need? *please wait while i draw the figure

1. anonymous

|dw:1327633952599:dw|

2. anonymous

2(22/7)r = (44/7)(15)=660/7feet^2 this is the bottem of the container (ill make it into decimals later)

3. anonymous

oh sry :P

4. anonymous

that is circumference of the bottem. Now we'll find the area of the middle section of the silo by multiplying it by 40 to get (660/7)(40)=26400/7 its more accurate to wait till the very end to round it off but if your still in high school then i guess you can round it off to 2 dec one time

5. anonymous

ok now to find the area of the bottem (22/7)r^2 (22/7)(15)^2 (22/7)(225) 4950/7

6. anonymous

okay so, the circumference is 94.28?

7. anonymous

94.29 not 94.28

8. anonymous

okay:) so the middle part is 3771.42, right?

9. anonymous

no its 3771.43 because 3771.428 is closer to 3771.43 than 3771.42

10. anonymous

sorry :p so, on the 3rd explanation what do you mean by bottom?

11. anonymous

the bottom of the silo, in other words the circle with radius 15

12. anonymous

with the circumference of 94.3?

13. anonymous

yes

14. anonymous

but make it two dec places not 1

15. anonymous

okay. so do i need to do anythign wih that triangle above the silo??

16. anonymous

for the area of the middle section dont use fractions then put 94.29x40 = 3771.6

17. anonymous

yes you do were actually only half way through this question

18. anonymous

okay.

19. anonymous

and the area for the bottom is 4950/7 = 707.14

20. anonymous

bottom of silo?

21. anonymous

si :)

22. anonymous

lol okay:) so now the pyramid thing. what ami supposed to do?

23. anonymous

for the cone at the top now this is just something u have to learn. A cone is also a semi circle and the 17feet is the radius of that semi circle

24. anonymous

okay

25. anonymous

so (1/2)(22/7)r^2 (11/7)(17^2) (11/7)(289) 3179/7 454.14

26. anonymous

whats that?

27. anonymous

the area of the pyramid at the top (cone) which is 454.14feet^2

28. anonymous

okay:)

29. anonymous

u understood wat i did?

30. anonymous

31. anonymous

$1/2( \pi r ^{2})$

32. anonymous

|dw:1327636571579:dw| so we find the area of the circle and then divide it by 2 using that formulae

33. anonymous

okay. :) so now we add both answers to get the whole thing, right?

34. anonymous

i see.

35. anonymous

all 3 yes

36. anonymous

3? we have the bottom of silo and pyramid.

37. anonymous

oh

38. anonymous

also the middle section

39. anonymous

454+3771+707.14?

40. anonymous

where u got 454? and it is 3771.6

41. anonymous

sorryabout the .6:) i thought the 454 was the area of the pyramid?

42. anonymous

oh yes my bad and its 454.14 feet dont forget about the dec places

43. anonymous

all right. :)

44. anonymous

and then we divide by 400?

45. anonymous

so 707.14+454.14+3771.6= 4932.88feet^2

46. anonymous

and yes

47. anonymous

yes. :)

48. anonymous

therefore to conclude this confusing and long question 4932.88/400= 12.3322 gallons

49. anonymous

also dont forget to put units and decimal

50. anonymous

yes. thank you hawkcrimson. for the patience? lol thanks:) and i won't forget te decimals :)

51. anonymous

im watching u like a hawk so u better not :P

52. anonymous

bahahaha lol. i won't :D

53. anonymous

kk take care bye

54. anonymous

bye and thanks:)