Question P6 Work backwards from volume or area
A cuboid has volume 480 cm³, length 15 cm and width 8 cm. Find its height.
Answer
4 cm
Work backwards from volume or area
Use the known area or volume to find the missing measurement.
In this one. Volume is the area of one layer multiplied by the height. Divide by the base area to find the missing height.
The question gives a cuboid's volume with two dimensions and asks for the third, or gives the volume with one length and asks for a face area. A square's area given with its side asked for belongs here too.
Children divide the volume by a length lying inside the face they want, instead of the length that runs into it, and get the wrong kind of measurement.
Worked examples of all 33 patterns and skills, in a booklet you can print.