Question

Hello again everyone. I have another mathematics assignment I would like someone to help me check. Thank you to anyone that helps. :)

1.) Find the volume of the given pyramid. H= 7 yd B= 7 yd and L= 9 yd
A. 147 yd.^3
B. 175 yd.^3
C. 221 yd.^3
D. 441 yd.^3
My answer - Not sure, hopping someone can help walk me through this. My answer was 114.

2. Find the volume of a square pyramid with a base length of 9 cm and a height of 4 cm.
A. 324 cm. ^3
B. 108 cm. ^3
C. 36 cm. ^3
D. 152 cm. ^3
My answer - B) 108 cm^3

3. Find the volume of the given cone. B=6 in and H=11 in
A. 320 in. ^3
B. 1244 in. ^3
C. 415 in. ^3
D. 622 in. ^3
My answer - I'm not sure if this is correct or not, but my answer is C) 415, if you estimate.
4. Find the volume of a cone with a radius of 10 mm and a height of 6 mm.
A. 628 mm. ^3
B. 600 mm. ^3
C. 1884 mm. ^3
D. 1254 mm. ^3
My answer - I wasn't sure if this was correct, but I estimated and got as close as 1, 884. If I am incorrect, please walk me through this.

5. find the lateral area of a cone with a radius of 7 ft and a slant height of 13 ft. use 3.14 for π and round to the nearest whole number.
A. 439
B. 324
C. 572
D. 286
My answer - B) 324 ft^2

6. Find the surface area of a square pyramid with a base length of 11 cm and a slant height of 15cm
A. 472
B. 451
C. 781
D. 330
My answer - A) 472 cm^2

7. find the surface area of the cylinder. Use the diagram of the cylinder to answer the question. Use 3.14 for π and round to the nearest whole number. Radius= 8in and height= 8in
A. 2,010
B. 402
C. 804
D. 603
My answer - C) 804 in^2
8. find the volume of the cylinder. Radius= 8in and height= 8in
A. 1,608
B. 2,846
C. 6,431
D. 401
My answer - A) 1,608 in^3

9. Find the volume of a rectangular prism with the following dimensions: Length= 5 mm
Base= 7 mm and the height= 3 mm
A. 142 mm ^3
B. 105 mm ^3
C. 126 mm ^3
D. 130 mm ^3
My answer - B) 105 mm^3

Thank you again to anyone who helps :)

- Merlana

Answer 1

All of these are very simple formulas, and with a calculator..

Answer 2

Volume of a pyramid = (1/3)(area of base)(height)
In #1, you don't say what L, B, and H represent.
So once you decide, plug in the values and see what you get
My answer would be (1/3)(7)(7)(9)
which is not 114
#2, correct
#3, correct to the nearest whole unit
#4. no
#5. The surface area of a cone is πrl, where l is the slant height
so Area = π(7)(13) = 285.9
I you want to include the base, add another π(7^2), but lateral area to me means without the base
your answer does not match any of these
#6. I see a correct answer if we use only the 4 triangles, and a correct answer if we include the square base
Yours does not match either
#7 correct
#8. correct

#9. correct , that was the easiest one