The exterior dimensions of a saef are 90 cm x 50 cm x 30 cm. if the walls of the safe are 1.5 cm thick, what is the interior volume of that safe?
My guess:
Subtract 1.5 cm from 90 cm and from 50 cm and from 30 cm.
Then multiply to find the volume:
(90 - 1.5)(50 - 1.5)(30 - 1.5) = ?? cm
If I'm wrong, another teacher will correct me.
=)
To find the interior volume of the safe, you are correct in subtracting the thickness of the walls from each exterior dimension. And then you can calculate the volume by multiplying the resulting dimensions together.
So, let's subtract 1.5 cm from each exterior dimension:
90 cm - 1.5 cm = 88.5 cm
50 cm - 1.5 cm = 48.5 cm
30 cm - 1.5 cm = 28.5 cm
Now, multiply these dimensions together to find the interior volume:
88.5 cm * 48.5 cm * 28.5 cm = 120,001.25 cm³
Therefore, the interior volume of the safe is 120,001.25 cm³.