SAHMom wrote:Hi, just a note in case there is any panic mode activated. The above solution pricked my interest due to its complexity and I think Ice Watch has proven the exact dimensions and areas using Pythagoras' Theorem (PT). But as P6 are not expected to learn and use the PT, I would like to think that the question might have been overlooked by the setter and it is not his/her initial intention to have the solution using the PT. I made a 12cm by 12 cm paper and did like the folding and the bottom edge did look exactly like cut into 3 equal parts of 4cm. As a parent of P6 kid, I would just point out the error to the teacher but will not go beyond the classroom and teach my kid on the above. At most, I will rephrase the question to finding "an estimate" of the shaded area and use TianZhu's working earlier if I really want my P6 kid to solve it.Ice watch wrote:tanxexy wrote:Please help on this question from ACS P5 2014 SA2:

x=3.96 <---------------【refer to the picture below】

2*3.96*7 = 55.44 <---【4 triangles area】

12*12 = 144 <---------【square area】

144 - 55.44 =88.56 cm^2【 the total area of the shaded part 】

Fully agree w u SAHMom. The Q itself is something "wrong", cos theoretically the bottom triangle is not an ideal "equilateral triangle". And these verification stuff is definitely beyond of the pri. scope.... too bad.