Final answer:
The volume of the rectangular block with dimensions 8cm by 5cm by 4cm is calculated by multiplying these numbers, resulting in a volume of 160 cubic centimeters.
Step-by-step explanation:
To calculate the volume of a rectangular block, you use the formula for volume which is Length × Width × Height. Given the dimensions of the block as 8cm by 5cm by 4cm, the volume can be found by multiplying these dimensions together:
Volume = 8cm × 5cm × 4cm
Volume = 40cm × 4cm
Volume = 160cm³
Therefore, the volume of the block is 160 cubic centimeters.