4 Brianne spins these two spinners. a Draw a sample space diagram to show all the possible outcomes. How many are there? b Work out the probability of Spinner 1 2 3 1 1 Spinner 2 3 4 2 6 2 4 Q4a hint 2 6 Put spinner 1 on the horizontal axis and spinner 2 on the vertical axis. i a 3 ii one number being half the other. Q4d hint iii both numbers being at least 2. c Which is more likely: two even numbers or two odd numbers? d Brianne spins the two spinners and adds the two numbers together. Draw a new sample space diagram to show the scores. e Which score is most likely? f What is the probability of scoring at least 4? 5 Each of these spinners is spun once. a Which spinner is more likely to land on blue? b Which spinner is more likely to land on red? c Work out P(grey) for each spinner. What do you notice? 6 16 people go to a knitting group. 13 people go to a sewing group. 9 people go to a knitting and sewing group. a Copy the Venn diagram. Spinner A Spinner B Use the same axes. For the result 1, 2, the score is 1 + 2 = 3 Q5a hint Compare the probabilities. For spinner A, P(blue) = For spinner B, P(blue) = knitting u u 4 = 8 u u 4 = 8 sewing i Write the number for knitting and sewing in the section where the circles overlap. ii How many people need to go in the rest of the knitting circle? Q6a ii hint The total in the whole knitting circle needs to be 16. iii How many people need to go in the rest of the sewing circle? b What is the probability that a person chosen at random goes to a i knitting and sewing group ii knitting group only? 7 This fair spinner is spun once. It is a fair spinner because it is equally likely to land on any edge. a How many possible outcomes are there? b Work out i P(blue) Q7a hint How many edges are there? Q7b i hint What fraction of the spinner is blue? Q7b v hint ii P(red) iii P(blue or red) iv P(red or yellow) v P(not blue) vi P(not yellow) 8 Problem-solving 3 1 For this spinner P(red) = 8 and P(blue) = 8. What is the probability of the spinner not landing on blue or red? P(blue) = 1 6 P(not blue) = 1 − 1 = 6 u u Q8 hint Copy the spinner and colour the blue and red sectors. Unit 8 Probability 192