2c Statement Statement The distribution of secondary school students correct with correct with full is NOT close to normal. It is closer to be a some justification. uniform distribution with very much the same justification. numbers at year 9, 10 and 11 with a small decrease in year 12 and year 13. No modal central value. An approximate sketch graph would be useful. Question Evidence Achievement (u) Merit (r) Excellence (t) Apply probability Apply probability methods, using methods, using Apply probability relational thinking, in extended abstract methods in solving problems. thinking, in solving solving problems. problems. Correct 3a 0.55 probability calculated. 3b 0 Correct probability calculated. 3c Correct probability calculated. 3d P (Zoe won in next 3 points) A correct Correct probability Correct probability = probability for Zoe winning in calculated. = 0.686125 calculated. next 3 points Reqd Prob = calculated. = 0.117 3e P (Zoe won on first point) = .55 A correct Total probability Correct probability probability calculated for a calculated. P (Zoe won on third point) calculated. faulty part. = = 0.136125 Reqd prob = = 0.802 3f P( BZB+ BBZ) A correct Correct total = + probability probability = calculated. calculated. 3g Correct probability written.
2c The distribution of secondary school students is NOT close to normal. It is closer to be a uniform distribution with very much the same numbers at year 9, 10 and 11 with a small decrease in year 12 and year 13. No modal central value. An approximate sketch graph would be useful. Statement correct with some justification. Statement correct with full justification. Question Evidence Achievement (u) Merit (r) Excellence (t) Apply probability methods in solving problems. Apply probability methods, using relational thinking, in solving problems. Apply probability methods, using extended abstract thinking, in solving problems. 3a 0.55 Correct probability calculated. 3b 0 Correct probability calculated. 3c Correct probability calculated. 3d P (Zoe won in next 3 points) = = 0.686125 Reqd Prob = = 0.117 A correct probability calculated. Correct probability for Zoe winning in next 3 points calculated. Correct probability calculated. 3e P (Zoe won on first point) = .55 P (Zoe won on third point) = = 0.136125 Reqd prob = = 0.802 A correct probability calculated. Total probability calculated for a faulty part. Correct probability calculated. 3f P( BZB+ BBZ) = + = A correct probability calculated. Correct total probability calculated. 3g Correct probability written.
2012_eoy_level_2_probability_exam.docx