Level 2
How many different handshakes can be made in a group of 21 students, assuming that each student shakes hand with every other student only once?
Level 3 PSLE
Fong wanted to build a set of steps with 1-cm cubes. The figures show how he built the steps from a height of 2 cm to 3 cm to 4 cm. If Fong continued building the steps in this way, what would be the height of the set of steps that had 135 cubes? Express your answer in cm.
Level 3 PSLE
Fong wanted to build a set of steps with 1-cm cubes. The figures show how he built the steps from a height of 2 cm to 3 cm to 4 cm. If Fong continued building the steps in this way, what would be the height of the set of steps that had 135 cubes? Express your answer in cm.
Level 3
In a table-tennis competition, every player plays against every other player twice. Every player plays the same number of games. There are a total of 56 games played. How many players are there?
