## anonymous one year ago The population of mathville is 5.6×10³. The population of algeville is 1.3×10⁴. How many people are the in algeville ? PLZZ HELP !!

1. anonymous

The population is the amount of people, so there would be $1.3*10^4$ people. Which is the same as 130000.

2. anonymous

Should I divide or subtract since its asking how many "more" people are there in algeville ?

3. skullpatrol

subtract to find the difference between the two populations

4. anonymous

@skullpatrol since its subtracting scientific notation it would be 5.6×10³ - 1.3×10⁴ ?

5. skullpatrol

yes

6. anonymous

You should subtract 1.3×10⁴-5.6×10³

7. skullpatrol

but change the numbers so they are easier to work with

8. skullpatrol

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9. skullpatrol

Can you handle it from here?

10. anonymous

@skullpatrol I never actually thought of doing that until now because at schooll my math teachers taught me to move the decimal which makes the exponent decrease by one for example instead of 1.3 it would be 13. Because the decimal is moved to right then you would subtract 1 from the ³

11. skullpatrol

yes you can do it that way too :-)

12. anonymous

I subtracted 130000-56000 and I got 7400

13. skullpatrol

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14. skullpatrol

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15. skullpatrol

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16. anonymous

@skull patrol since it's a word problem my answer would be - "there is 7,400 more people in algeville than Mathville" ?

17. skullpatrol

yes

18. anonymous

Alrighty THANKKKKKK you so MUCH !!!! @skullpatrol really appreciated your help :)

19. skullpatrol

20. anonymous

@skullpatrol can you help me with one more problem ?

21. anonymous

$1.3*10^4-5.6*10*3=1.3*10*10^3-5.6*10^3=\left( 1.3*10-5.6 \right)*10^3$ $=\left( 13.0-5.6 \right)*10^3=7.4*10^3=\frac{ 74 }{ 10 }*1000=7400$

22. anonymous

Thanks @surjithayer

23. anonymous

yw

24. anonymous

correction 5.*10^3 not 5.6*10*3

25. anonymous

@skullpatrol can you help me with this one ~ total health care costs in the United states in 2003 was $1.3 trillion . The U.S population was$290.9 million . What was the average amount spent per person on helthcare ?

26. skullpatrol

Any ideas?

27. anonymous

Sorry typo i meant 290.9 million

28. skullpatrol

I see np :-)

29. anonymous

I was thinking of turning 1.7 to 17,000,000,000,000

30. skullpatrol

What does " the average amount spent per person on healthcare" mean to you?

31. anonymous

Um I think it means like the the amount spent on each person

32. skullpatrol

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33. anonymous

So it would be 1.7 trillion ÷ 290.9

34. skullpatrol

Yes, but you missed the million on 290.9 million

35. skullpatrol

Also a trillion is $$\Huge 10^{12}$$

36. skullpatrol

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37. anonymous

Alrighty so it would be 290.9×10^6 ÷ 1.3 × 10^11 ?

38. skullpatrol

10^12

39. anonymous

40. skullpatrol

np

41. anonymous

When I divided 290.9 by 1.3 I got 223.769231

42. skullpatrol

yes

43. anonymous

But isn't it too large ?

44. skullpatrol

nope

45. anonymous

Kk so when I subtracted my exponents I got -6

46. skullpatrol

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47. skullpatrol

check the word "trillion"

48. anonymous

Alrighty so the average person payed $223 ? 49. anonymous Wait isn't the 290.9 supposed to be on top ? 50. anonymous Are you there @skullpatrol? 51. skullpatrol you want dollars per person 52. anonymous Yeah so it's$223 per person or \$23.30 ?

53. skullpatrol

what about the powers of 10?

54. anonymous

223×10^-6 because 6-12 = -6

55. anonymous

I got it now

56. anonymous

Thanks again @skullpatrol