Year 5 extension

1. Ana has five digit cards: 3, 7, 0, 5 and 9. She uses every card once to make a five-digit number. What is the largest even number she can make?
2. At 6 am in Queenstown the temperature is −4 °C. It rises by 3 °C every hour until noon, then falls by 2 °C every hour. What is the temperature at 3 pm?
3. Wiremu makes a row of squares with matchsticks. 1 square uses 4 matchsticks, 2 squares in a row use 7, and 3 squares in a row use 10. How many matchsticks does he need for a row of 20 squares?
4. Aroha thinks of a number. She multiplies it by 6, subtracts 6, then halves the result. Her answer is 21. What number did she start with?
5. Tama writes a number between 3 and 4 with two digits after the decimal point. When he swaps those two digits, his number gets bigger by 0.27. Which of these could be Tama's number?
6. A rectangle has a perimeter of 24 cm. Its side lengths are whole numbers of centimetres. What is the largest area it can have?
7. Mere buys 3 pies and 2 drinks for $17.00. Hemi buys 2 pies and 3 drinks for $15.50. All pies cost the same and all drinks cost the same. How much is one pie?
8. A large cube is built from 27 small cubes, 3 along each edge. The outside of the large cube is painted blue. How many small cubes have blue paint on exactly two faces?
9. In a class of 28 students at a Hamilton school, 17 play netball, 15 play football, and 4 play neither sport. How many students play both?
10. Rawiri rolls two ordinary six-sided dice and adds the two numbers. What is the probability that the total is 7?