Skip to content

Course home

4.2 Statistical distributions (A-level only)

4.2 Statistical distributions (A-level only)

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233
Question 124

The operational lifespan, in minutes, of high-performance lithium batteries for two different drone models follows normal distributions. Type Alpha batteries have a mean lifespan of 1250 minutes and a standard deviation of 45 minutes. Type Beta batteries have a mean lifespan of 1180 minutes and a standard deviation of 55 minutes.

One battery of each type is selected at random.

a.

Determine the probability that the Type Alpha battery lasts longer than the Type Beta battery.

[5]
b.

A fleet of drones is fitted with four Type Alpha and four Type Beta batteries, all operating independently.

Calculate the probability that the total combined lifespan of these eight batteries is greater than 9850 minutes.

[5]
Markscheme

4.2 Statistical distributions (A-level only) Questions

  1. A Level
  2. /Maths
  3. /4.2 Statistical distributions (A-level only)

328 exam-style questions on WJEC A Level Maths 4.2 Statistical distributions (A-level only), covering 4.2.1 Statistical distributions (A-level only), 4.2.2 Statistical distributions (A-level only), and 4.2.3 Statistical distributions (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

Question bank