Question

A rectangular prism is truncated removing 20% of its height. The original height of the prism was 100 inches and it has a length of 5 inches and a width of 10 inches. What is the volume of the truncated prism?
Answer

2,000 in3

3,000 in3

4,000 in3

5,000 in3

for this one i got 3,000?

Answer 1

the height was 100inches
now to take off 20% of 100 we use:
\[\LARGE 100(1-20\%)=\]
\[\LARGE 100-100\cdot {20\over 100 }=\]
\[\LARGE 100-20=80\]
so we have its new cordinates:
height:
H=80 inches
Length 5 inches
and width 10 inches

now we have:

Although the picture doesn't fit with its dimensions, let's assume they're ok. :)
and we have the formula for Volume:
\[\LARGE V=l\cdot h\cdot w\]
\[\LARGE V=5 \;\; inch \cdot 80 \;\; innch \cdot 10\;\;inch\]
can you do it now ? :)