Skip to content

Course home

2.4.2 The Normal distribution (A-level only)

2.4.2 The Normal distribution (A-level only)

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256
Question 149

The mass of beans in a tin filled by a machine, in grams, is Normally distributed with mean 415 g and standard deviation 3.4 g.

a.

Find the probability that a randomly chosen tin contains less than 409 g of beans. Give your answer to 3 significant figures.

[1]
b.

The company suspects that the machine is now filling tins to a mean mass of less than 415 g. A random sample of 20 tins is taken, and the mean mass of beans in the sample is 413 g.

Stating your hypotheses clearly, carry out a test at the 1% significance level to investigate the company's suspicion. You may assume that the standard deviation is still 3.4 g.

[4]
Markscheme

2.4.2 The Normal distribution (A-level only) Questions

  1. A Level
  2. /Maths
  3. /2.4.2 The Normal distribution (A-level only)

351 exam-style questions on AQA A Level Maths 2.4.2 The Normal distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

Question bank