9,899 = 206x
He divided by 206
He got 48.053 and rounded up to 49
My using the equation, we can see that he is correct.
With the number being x, we have 3x^2>6(x/9). Expanding, we get 3x^2>6x/9 and 3x^2>2x/3. Dividing by x, we get 3x>2/3 and dividing by 3 we get x>2/9
The answer for the exercise is the third option, which is: Hexagon.
The explanation is shown below:
As you can see in the figure attached, the cross section is a polygon of six sides and six angles. Therefore, it has six vertexes. In geometry, this type of polygon is known as "Hexagon".
The fastest way is to just use a scientific calculator.
To do it without a calculator, use prime factorization.
I'll only do the second one which is the answer.
27 x 8
= 3^3 x 2^3 = 6^3
Which is a perfect cube.