HSC Countdown 2

What is the range of scores in this class test?

• 27

• 28

• 29

• 35

Find the median score for the boys in this class test.

• 12

• 15

• 19

• 21

The distance-time graph for a moving object is shown. What is the speed of the object in kilometres per hour?

• 3 km/h

• 14 km/h

• 50 km/h

• 180 km/h

• The mean increased and the standard deviation decreased.

• The mean increased and the standard deviation increased.

• The mean decreased and the standard deviation decreased.

• The mean decreased and the standard deviation increased.

Sonia has written letters to four of her friends and sealed the letters in envelopes. Now she does not know which envelope contains which letter!!! :(

If Sonia addresses the envelopes to her four friends at random, which is the probability that each envelope contains the correct letter?

• $\frac{1}{256}$

• $\frac{1}{24}$

• $\frac{1}{16}$

• $\frac{1}{4}$

Which of the following is the correct simplification of

 $8x^3-5x^3$  

•  $3x^6$  

•  $3x^3$  

•  $3x$  

• 3

What is the total payable?

• $1029.02

• $1224.02

• $102902.15

• $103097.15

Which one of the following could be the graph of

 $y=3x+1$  

• A

• B

• C

• D

Sarah has two packets of jelly beans. Each packet contains one black and five yellow jelly beans. Sarah takes one jelly bean from each packet without looking.

What is the probability that both jelly beans are black?

• $\frac{1}{36}$

• $\frac{1}{12}$

• $\frac{1}{6}$

• $\frac{1}{3}$

• $1265

• $37 950

• $390 000

• $455 400