Question

Tyer brought a pencil holder in the shape of a triangular prism, as a gag gift for his friend's birthday.

(1) He fills the pencil holder with sand before he wraps it to make it feel like a heavy, expensive gift. How much sand will he need to "borrow" from his sister's sandbox to fill the pencil holder?

(2) What is the minimum amount of Saran wrap that Tyler will need to cover the pencil holder, to ensure that no sand leaks out?

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Answer 1

Answer: 10.5 cubic inches.

Explanation:

Volume of pencil holder = Base x Height

Base (I think it's an isosceles triangle) =
`(b h)/(2)` =
`(3 divide2)/(2)` = 3

Base x Height = 3 x 3.5

= 10.5 in³