MHB NAP Yr 9 Example Test: Numeracy Q28 - 47.5 cm?

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Question 28 of the NAP Year 9 Numeracy test presents a discrepancy where one participant calculated an area of 47.5 cm², while others confirmed it as 46 cm². The correct approach involves calculating the areas of all rectangular faces and adding them to the given areas of triangular faces. A detailed breakdown of the calculations shows that the total area sums to 46 m², emphasizing the importance of unit conversion. Despite attempts to identify scenarios leading to the 47.5 cm² answer, no valid reasoning was found. Accurate calculations and unit awareness are crucial for solving such problems correctly.
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I get 46 cm². Can you post your work so we can see what you did wrong?
 

I get 46 too, but in meters and not in centimeters! (which makes a huge difference) (Sweating)

Areas of triangular faces are already given. We just need to find separate areas of all rectangular faces and add all triangular-face-areas to rectangular-face-areas in order to get the total area.

$$3+3+(5 \times 2.5)+(5 \times 2.5)+(5 \times 3) = 46 \text{m}^{2}$$

Also, I tried many experiments to find a situation where someone gets confused and gets the answer as $$47.5$$ by mistake, but found no such situation!
 

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