Cover of the textbook Outcomes Advanced - Student's Book

The key answer of exercise 5

The key to exercise solutions in chapter 7 - Vital statistics for the textbook Outcomes Advanced - Student's Book with authors Carol Nuttall and Amanda French from National Geographic Learning

Question

Work in pairs. Why were the groups of numbers and statistics below mentioned? Listen again and check your ideas.

Answer

  1. Talking about people’s understanding of probability 60% of people say that if you throw a coin twice the probability of getting two heads is 50% when in fact it’s 25%.
  2. Talking about sample size 50 people interviewed through social media is not as good as 5,000 people chosen at random.
  3. This shows how the relative figures are calculated for Company A Initially produces 10,000 a year and this rises to 12,000 – an increase of 20%.
  4. This shows how the relative figures are calculated for Company B Initially produces 1,000 a year and the next year 1,400 – a 40% increase.
  5. Comparing the relative increases, Company B can claim to be performing twice as well as its rival but in absolute terms it produces 1,600 fewer extra units over the last year than Company A.
  6. 50% – probability each time you throw a head