## anonymous 4 years ago If gas costs $3.65 per gallon at a local service station, how many cubic feet of gas can a customer buy with$40 ?

1. precal

40/3.65=10.95 gallons

2. anonymous

how far can the customer drive if the car gets 4 miles per cubic foot of gas?

3. precal

4 miles per gallon??? Horrible mileage.....

4. anonymous

the first answer was rejected, the 10.95

5. anonymous

they want the answer in ft^3, i guess

6. precal

weird.... I was just thinking of it like in the real world. I have $40 dollars and I can only by approx 10.9 gallons at 3.65 maybe you need to input it as 10.9 (do you have instructions on what place to round to?) 7. anonymous no. 8. anonymous well can you help me with 4 other questions please 9. anonymous i have this The compound interest formula is F = P(1 + i)^n where F is the total amount due, P is the initial cost or amount of money, i is the interest rate, and n is the number of periods interest is computed. A student purchases a$1300 laptop computer for school. The deal does not require payment until 2 years later. If interest is computed monthly, how much does the student have to pay at the end of 2 years? The monthly interest rate is 1.8 percent.

10. precal

ok I will try, what do you have?

11. precal

P=1300 i=.018 n = 12 because it is monthly but n = 24 because of 2 years F=1300(1+.018)^24 compute F

12. anonymous

did you get 1994?

13. precal

and 76 cents

14. precal

That would be a bad deal, that means that person is willing to pay 694.76 to borrow 1300

15. precal

yes 1994.76

16. anonymous

my damn software rejected the answer

17. precal

I still think the directions somewhere has to say how to input the solutions. Decimals are tricky. I am given you real world solutions but if the instructions are to round to the nearest whole number 1995 would be the only accepted answer.

18. anonymous

ok what about this one A copper pipe, used for plumbing from the water main to a house, is 5 meters long and has a circular cross-section 3.2 cm in diameter. There is a 2.4 cm diameter hole in the center of the cross-section for the entire length of the rod. What is the volume of copper in the rod in cubic inches?

19. precal

were you given a picture? Upload it by attaching the file.

20. anonymous

21. anonymous

yea theres the picture for the last problem

22. precal

V=Bh B is a circle so B is pi(r^2) $V=\pi r^2h$

23. anonymous

so v=pi(5^2)(3.2)?

24. precal

picture stated 1 gallon = 231 cubic inch we sort of needed that info earlier

25. anonymous

oh sorry

26. precal

|dw:1328667396808:dw|

27. precal

original solution is 10.95*231=2529.45 cubic inches

28. precal

|dw:1328667597151:dw| I think you will have a circle within a circle, but you should not be using diameter. Take half of the diameter and that is your radius

29. anonymous

3.2/2=1.6, is that right

30. precal

yes if d=3.2 then r = 1.6

31. anonymous

so is h the 2.4?

32. precal

no 5 is the height (it you stand the pipe up you will see that it is 5)