Question

1. which expression can not be used to show the volume of this solid figure? a. 5x3 b. 9x5 c. 15x3 d. 5x3x3

Explanation:

Step1: Identify dimensions of the rectangular - prism

The solid figure is a rectangular - prism. Counting the unit cubes, we find the length is 5 cm, the width is 3 cm, and the height is 3 cm.

Step2: Recall the volume formula for a rectangular - prism

The volume formula for a rectangular - prism is $V = l\times w\times h$, where $l$ is the length, $w$ is the width, and $h$ is the height. Here, $V=5\times3\times3$. Also, $5\times3$ gives the area of the base, and multiplying by the height 3 gives $V=(5\times3)\times3 = 15\times3$.

Step3: Analyze each option

• Option a: $5\times3$ gives the area of one of the bases, not the volume.
• Option b: $9\times5$ is not equivalent to the volume calculation.
• Option c: $15\times3=(5\times3)\times3$ which is a correct way to calculate the volume.
• Option d: $5\times3\times3$ is the direct application of the volume formula $V = l\times w\times h$.

Answer:

A. $5\times3$, B. $9\times5$