Square tiles are laid to make hollow square frames: a single ring of tiles around an empty middle. Step 1 is a frame 3 tiles long on each side and uses 8 tiles. Step 2 is 4 tiles long on each side and uses 12 tiles. Step 3 is 5 tiles long on each side and uses 16 tiles. The pattern continues in the same way. How many tiles are in step 10?
A beekeeper weighed the honey taken from each of her four hives in spring and again in autumn. Which hive gave a total for the two seasons closest to 50 kg?
Zara filled three cans, one black, one white and one silver, with the same amount of water at 18 °C. She placed them side by side in the sun and measured the water temperature in each can after 30 minutes. Which conclusion is best supported by her results?
Can
Water temperature after 30 minutes
Black
34 °C
White
27 °C
Silver
25 °C
AA.
In Zara's test, the water in the black can warmed up the most.
BB.
Silver cans keep drinks colder than other cans in a fridge.
CC.
Black objects always become hotter than objects of any other colour.
DD.
The colour of the can made no difference, because all three cans warmed up.
In a puzzle, ■ means 'multiply the two numbers, then subtract the larger one', and ▲ means 'add the two numbers, then halve the result'. For example, 5 ■ 3 = 15 − 5 = 10, and 4 ▲ 8 = 6.
A school play sold three kinds of ticket: adult $12, child $6, and family $30 (one family ticket lets in 2 adults and 2 children). The table shows how many of each kind were sold. On which day did ticket sales bring in the most money?
A jar holds red and blue marbles in the ratio 3 : 5. Ana adds 12 red marbles, and the ratio of red to blue becomes 3 : 4. She then adds just enough blue marbles to make the ratio 3 : 5 again. How many marbles are in the jar now?