1. **Problem:** Two students build boxes with the same total surface area.
- Student 1 makes a cube with edge length $60$ cm.
- Student 2 makes a rectangular prism with width $w$ cm, height $30$ cm, and depth $45$ cm.
We need to determine which box has the greater volume and by how much.
2. **Find the surface area of the cube.**
The formula for the surface area of a cube is
$$S=6s^2$$
where $s$ is the edge length.
Substitute $s=60$:
$$S=6(60)^2=6(3600)=21600$$
So the cube’s surface area is $21600$ square centimeters.
3. **Set the prism’s surface area equal to the cube’s surface area.**
The surface area of a rectangular prism is
$$S=2(lw+lh+wh)$$
Here the dimensions are $w$, $30$, and $45$, so
$$21600=2(w\cdot 30+w\cdot 45+30\cdot 45)$$
Simplify inside the parentheses:
$$21600=2(30w+45w+1350)$$
$$21600=2(75w+1350)$$
Divide both sides by $2$:
$$\frac{21600}{2}=\frac{2(75w+1350)}{2}$$
$$\cancel{2}\,10800=\cancel{2}(75w+1350)$$
$$10800=75w+1350$$
4. **Solve for $w$.**
Subtract $1350$ from both sides:
$$10800-1350=75w$$
$$9450=75w$$
Divide both sides by $75$:
$$\frac{9450}{75}=\frac{75w}{75}$$
$$\cancel{75}\,126=\cancel{75}w$$
$$w=126$$
5. **Find the volume of each box.**
Volume of the cube:
$$V= s^3 = 60^3 = 216000$$
So the cube has volume $216000$ cubic centimeters.
Volume of the rectangular prism:
$$V=lwh$$
$$V=126\cdot 30\cdot 45$$
$$126\cdot 30=3780$$
$$3780\cdot 45=170100$$
So the prism has volume $170100$ cubic centimeters.
6. **Compare the volumes.**
$$216000-170100=45900$$
The cube has the greater volume.
7. **Final answer:** The **cube** has the greater volume, and its volume is **45900 cubic centimeters** greater than the rectangular prism’s volume.
Hidden Space 2Fe6F5
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