Tùng has the seven coloured tangram pieces shown. He arranges the pieces without overlaps. Which pictured arrangement cannot be made from those seven pieces?
Mary has the number grid shown. Each circle must contain the sum of the four numbers in the squares touching it. What is the largest number she will put in a circle?
Ann, Bin, Joly and Lio play a game. In the last round, Ann scores 4 points, Bin 2, Joly 6 and Lio 5. They finish with equal totals. What was their order of scores before the last round, starting with the highest?
Ben has a loop of cord threaded through three stacked cards as shown. Each card has a white upper face and a grey lower face. He spreads the cards on the table. Which picture can show his loop and cards?
Geometry is all around us. For example, a blackboard is rectangular, a wall clock circular, a window square and a hair bow triangular. Look around and give more examples of objects whose shapes resemble these examples.
A kangaroo goes from a bench to a pond in 7 jumps of 6 m each. On the return journey it makes 4 jumps of 3 m and some jumps of 2 m. How many 2 m jumps does it make?
Cat wants to catch Mouse and Rat. Mouse always moves 1 cell left per jump, Rat always moves 1 cell right, and Cat can jump 2 cells left or right. All three jump simultaneously. If Cat decides to catch Rat first, what is the least number of jumps needed to catch both?