P5 Area and volume foundations
liquid volume in a tank
A rectangular tank is 8 cm long, 5 cm wide and filled to a height of 6 cm. Find the volume of water.
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The pattern behind it: Area and volume foundations
Choose the matching base and perpendicular height, or count equal cube layers before multiplying dimensions.
In this one. Use the height of the liquid, which may differ from the tank height. The water forms a cuboid.
How to spot it
Look for shapes drawn on a dotted or squared grid, sharing a side or a vertex, with names like ABCD and ABE. Words like "grid", "dots" or "squares" alongside a request to compare areas or heights are the giveaway.
Common mistake
Children measure height by eye along the slanted side of a shape instead of counting the straight up-down grid distance from the base to the opposite vertex, which gives the wrong height whenever a side leans.
Try one like it
Standard area of a triangle A triangle has base 8 cm and perpendicular height 5 cm. Find its area.The 33 problem patterns
All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.
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