Math topic中文

Combined events

probability of simple combined events (including using possibility diagrams and tree diagrams, where appropriate)

Practice questions

  1. 1The masses of two batches of 400 steel bars produced by factory A and B were measured and recorded. The cumulative frequ…
  2. 2A bag contains 4 black coins, 7 red coins and 11 white coins. Two coins are drawn from the bag at random, one after anot…
  3. 3A bag contains 12 balls. 2 of the balls are red, n are green balls and the rest are blue balls. Eunice takes two balls f…
  4. 4A survey was carried out to find out the number of emails received in a week by each of a group of students. The table b…
  5. 5The cumulative frequency curve shows the marks obtained by the 120 students in a recent Mathematics Test. The maximum ma…
  6. 6The following stem-and-leaf diagram shows the marks obtained by 20 pupils in a class test that has a total mark of 50. S…
  7. 7In a class of 36 students, each student is either in a sports team or a performing arts club. Each student is also eithe…
  8. 8Charlotte the spider is walking along a web shaped like a 5-pointed star, shown in the figure below. The web has 5 outer…
  9. 9The stem and leaf diagram below shows the marks obtained by 30 students in a Science test marked out of 80 marks. Find t…
  10. 10In a game two dice are used. Die A has 2 blue faces and 4 yellow faces. Die B has 4 blue faces and 2 pink faces. The two…
  11. 11A game has two sets of eight icons. One icon from each set is randomly chosen to be displayed on each turn, starting wit…
  12. 12Jane had a box filled with 8 red pens, 4 blue pens and 6 green pens. She took out two pens at random, one after the othe…
  13. 13A box of chocolate contains 7 dark chocolates and 5 milk chocolates. Sufyan takes a chocolate, selected at random, from…
  14. 14The table shows the height, h cm, of 60 plants. Calculate an estimate of the standard deviation of the height of the pla…
  15. 15A bag contains 150 chips. There are 60 blue chips, x red chips and y green chips in the bag. The probability of drawing…
  16. 16The probabilities of Andrew, Ben and Caleb passing the driving test are 35\frac{3}{5}, 23\frac{2}{3} and 34\frac{3}{4} r…
  17. 17The box-and-whisker plots show the distribution of the masses (in grams) of eggs sold in Shop A and Shop B. There are 25…
  18. 18In a particular month, 21 people took a driving test. One of the 21 people is selected at random. The probability that i…
  19. 19A fitness centre has 16 employees. One of the 16 employees is selected at random. The probability that it is a woman wor…
  20. 20The cumulative frequency curve below illustrates the wait time of 240 customers who visited a bank. Use the graph to est…
  21. 21A carton contains 17 good apples and 3 rotten apples. A fruit seller picks three apples in random from the carton and pu…
  22. 22小王和小明玩一个游戏，规则如下：把分别写有11、22、33、44的四张卡片全都放入一个暗盒中，每次摇匀后每人摸出一张.算出这两张上的数字之“和”；当“和”为奇数时，小王胜，当“和”为偶数时，小明胜，玩了一会，小王对小…
  23. 23A box contains 9 apples of variety A and 7 apples of variety B. Two apples are taken from the box at random, without rep…
  24. 24A survey was carried out to find the amount of money spent by 100 customers in a supermarket. This information was group…
  25. 25The cumulative frequency curve shows the distribution of marks scored by 180 students in a Mathematics examination in 20…
  26. 26A city has people with Blood Types as follows: Type O 45% Type A 40% Type B 11% Type AB 4% Two persons are selected at r…
  27. 27The diagram shows a lucky draw spinner at a departmental store. The pointer is equally likely to stop at any of the sect…
  28. 28A box has 20 pots of plants. There are 5 pink pots, 9 blue pots and the remaining pots are green. (i) Two pots are taken…
  29. 29Five discs numbered 1, 3, 4, 6 and 7 are placed in a bag. Two disc are taken out of the bag at random without replacemen…
  30. 30The faces of each of two fair dice are numbered 11, 22, 33, 55, 77, and 88. When the two dice are tossed, what is…
  31. 31The masses of 40 oranges were measured. The cumulative frequency curve below shows the distribution of the masses. Use t…
  32. 32Students in a class were asked how many siblings they have. The results are shown in the table. The modal number of sibl…
  33. 33A drawer contains 2 blue socks and 6 white socks. Two socks are taken from the drawer at random without replacement. If…
  34. 34Each of two boxes contains three chips numbered 1, 2, and 3. A chip is drawn randomly from each box and the numbers on t…
  35. 35The amount of mass loss in kilograms of 200 members was recorded by Amazing Fitness Centre over a one year period. The c…
  36. 36一个袋中有3个红球和5个白球，不放回地连取2个球，求两个都是红球的概率。
  37. 37The histogram below shows the distribution of the scores of the participants from Potong Pasir Secondary School in a cur…
  38. 38In February 2021, a survey was carried out to find the number of days 500 patients stayed at a hospital. The graph shows…
  39. 39The table shows the colour of the pen 200 people took during a game. A person is selected at random. Find, as a percenta…
  40. 40The time spent by 60 students on social media in a week is recorded. The cumulative frequency curve below shows the dist…
  41. 41In a shooting game, the player has to shoot with a gun to capture a monster. The bullet from the gun has to land on a ci…
  42. 42Bag A has 4 green counters, 6 red counters and 2 yellow counters. Alice takes a counter at random from Bag A, notes its…
  43. 43A bag contains 15 red marbles, some blue marbles and some yellow marbles. A marble is chosen at random from the bag. The…