Eton King`s Scholarship 11+ Common Entrance Exam Maths Analysis

I will analyse the above maths question from the Eton King s Scholarship 2014 exam paper.

9 a) Given are 4 conditions, we know the 3 angles of the triangle in terms of x and y, we also know that AB=AC, which means this is a isosceles triangle (this is a must know). Therefore we get the first equation 2x+12y=8x+5y (careful, none of the given condition is an equation!). In order to solve x and y, we need another equation, which is the sum of the three angles is 180 (must know!). Then solving the two simultaneous equations, we can find x and the angle ABC.

9 b) similar to a), use the given conditions and sum=180 for all triangles in the graph, you can find the answer is 19.

10 a) derive that x=(20+5y)/7, remember that x>y, so try y=1,2,3, if the x calculated is an integer and greater than y, then bingo!

b) similar to a), have x+y+z=30, where x, y and z represent for 2p, 5p and 10p coins respectively.