Probability

A

100

Q7b

3 and 4

200

Q7e

P(2)=3/8

3/8 x 400 = 150 times

300

Q11a and b

a) correct table

b) 11/36

400

Q5a

A multiple of 3 is more likely because there are 3 outcomes. There are only 2 outcomes for a multiples of 7

500

Q14b

4 red = 1/5

1/5 = 4/20

20 counters in total now. 8 counters originally

Therefore 12 pink

B

100

Q1a

0.15

200

Q3b

0.32 because the greater number of spins is more accurate

300

Q5b

Even, prime, odd

400

12b

P(>30) = 0.25+0.35 = 0.6

0.6 x 60 = 36 nails 

500

Q15

72 x 0.15 = 10.8

C

100

Q7c

?

200

12a

1 - 0.15 - 0.2 - 0.25 - 0.35 = 0.05

300

Q9a and b

a) 1 - 6/21 = 15/21

b) 7/21

400

Q4a

Impossible

500

Q16

Sample space!

1/12

D

100

Q7a

2

200

Q1b

0.35 x 1500 = 525

300

Q2

P(3)+P(4)+P(5+) 

= 0.28+12+0.09

= 0.49

400

Q4b

Possible

500

Q10

Y

Not W because it doesn't have a 3

Not Z because it doesn't have a 2

Not X because the tallies don't add up to 20

E

100

Q7d

Even

200

Q3a

0.34 x 200 = 68

300

Q8

P(B) = 0.2

P(W)=0.5

P(R)=0

400

Q4c

Possible

500

Q6

Girls in play: 60 x 0.35 = 21

Boys who audition: 90-60=30

Boys in play: 30 x 0.6 = 18

Total = 21 + 18 = 39