Question

is my process correct?


1. I found the formula for the volume of a pyramid:

V = (1/3) × base area × height


2. Since the base is a rectangle, I can use the formula: B = length × width.

7 cm × 9cm = 63 cm.


3. Then I substituted the numbers 63 and 231 into the volume formula.

231 = (1/3) × 63 × h


4. Then I calculated 1/3 × 63.


1/3 × 63 = 63 ÷ 3 = 21.

231 = 21.


5.

Lastly, I divided 231 by 21.


H = 231 / 21 = 11 cm.


The height of the pyramid is 11 cm. (Double Check: 63 × 11 = 693 × 1/3 = 231 cm³.)

Answer 1

Yes — your process is correct and the height is 11 cm. A couple of tiny notational fixes:

- The base area is 7 cm × 9 cm = 63 cm² (not "63 cm").
- From V = (1/3)Bh with B = 63 cm² and V = 231 cm³ you get 231 = (1/3)·63·h, so 231 = 21·h (not "231 = 21").
- Then h = 231/21 = 11 cm.

Your final check (63 × 11 = 693; (1/3)·693 = 231 cm³) is correct.