## anonymous one year ago will fan and medal!! A cylindrical piece of iron pipe is shown below. The wall of the pipe is 1.25 inch thick: The figure shows a cylinder of height 16 inches and diameter 6 inches. What is the approximate inside volume of the pipe? 88 cubic inches 49 cubic inches 142 cubic inches 154 cubic inches

1. anonymous

Help

2. anonymous

@welshfella @Hero @acxbox22 @LegendarySadist @prowrestler @Zale101 @xavierbo2 @campbell_st @vera_ewing @bubbleslove1234

3. anonymous

Help

4. anonymous

hello?

5. campbell_st

so the pipe has an outer diameter of 6 inches so radius 3 inches an inner diameter of 6 inches - 2 x 1.25 so the inner diameter is 3.5 inches or radius 1.75 inches so find the area of the inner circle and then multiply by the height of 16 inches |dw:1439237745793:dw|

6. anonymous

How do i find the area of the inner circle?

7. anonymous

Im retarded im sorry

8. MattDuhHelper

multiply. cause its area

9. anonymous

so what do i multiply

10. campbell_st

well the area of a circle is $A = \pi r^2$ and you have your radius

11. campbell_st

so substitute and calculate the area... then multiply by the height

12. anonymous

ok sec

13. anonymous

so A=3.14x1.75x 16?

14. campbell_st

well you need to square the inner radius...

15. anonymous

so the inner radius is 9?

16. anonymous

Im so incompetent

17. campbell_st

the area of the inner circle is $A = \pi \times 1.75^2$ calculate the area then multiply by the height

18. anonymous

I got 9.616 @campbell_st

19. campbell_st

that's ok for the area, now multiply by the height

20. anonymous

153.86?

21. anonymous

@campbell_st

22. anonymous

lol its d thank you so much @campbell_st