VCE Biology free practice questions with answers
Read question 1 and its full worked answer from paper 1 of our 20-paper VCE Biology set, then download the 4-page PDF. These are original practice questions, not official past papers. Page updated 3 November 2026.
In a vaccine trial, 1000 volunteers received the vaccine and 1000 received a placebo.
Over the next season 10 vaccinated people and 157 placebo recipients developed the disease. Calculate the vaccine efficacy: (attack rate in unvaccinated − attack rate in vaccinated) ÷ attack rate in unvaccinated × 100.
A 6.37 %
B 99.0 %
C 14.7 %
D 93.6 %
Correct answer: D — 93.6 %
- attack rate (vaccinated) = 10 ÷ 1000 = 1 %; attack rate (placebo) = 157 ÷ 1000 = 15.7 %.
- efficacy = (15.7 − 1) ÷ 15.7 × 100 = 93.6 %
- Why the other options are wrong:
- A (6.37 %): gave the relative risk as a percentage instead of the reduction
- B (99.0 %): subtracted the vaccinated attack rate from 100
- C (14.7 %): gave the absolute risk reduction
Vaccine efficacy = reduction in the attack rate: (AR unvaccinated − AR vaccinated) ÷ AR unvaccinated × 100.
Your sample is downloading. Liked it? VCE Biology Paper 1 is the full paper: a full practice examination with Section A 40 multiple-choice, Section B 80 marks, 120 marks in all, 15 minutes reading time and 2 hours 30 minutes writing time, with a worked solution for every question.
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Questions about this sample
What is in the VCE Biology free sample?
The first 3 questions from paper 1 of the set, in the real exam layout, followed by the step-by-step worked answers. It is a 4-page PDF; this page shows question 1 with its answer.
How many full VCE Biology papers are there?
20 original papers for Victorian Year 12 students (VCE Units 3 and 4). Each is a full practice examination with Section A 40 multiple-choice, Section B 80 marks, 120 marks in all, 15 minutes reading time and 2 hours 30 minutes writing time, with a worked solution for every question. Papers start at A$15.99 and download instantly as a PDF.
Are these official past papers?
No. The sample is taken from our own original practice paper and is not an official past paper or affiliated with any exam authority.