• please explain part 3
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Worked Example 2 Dot Diagram RACTIS The dot diagram represents the masses, in kg, of 24 students. ATTENTION dot di . . An advantage of a do diapers that it is an easy way to dig small sets of data that dry dry contain many distinct walk A disadvantage is that if a 30 35 40 data is too large, the diagrams appear packed. (i) What is the most common mass? (ii) Calculate the percentage of students who have a mass of more than or equal to 32 kg. (iii) A student is selected at random. The probability that the student has a mass of at least x kg is 3. Find the value of x. (iv) Briefly describe the distribution of the data. Solution: (i) The most common mass is 32 kg. (ii) Percentage of students who have a mass of more than or equal to 32 kg 15 24 x 100% = 62.5% (iii) Number of students who have a mass of at least x kg =2 X 24 (since probability = 3) = 8 Since 4 + 2 + 1 +1 =8, . . . . . . . . . . . 25 30 35 .: Value of x = 34 (iv) The masses of the 24 students range from 25 kg to 40 kg. The masses are symmetrical about 32 kg. The extreme masses of 25 kg and 40 kg deviate considerably from the other masses recorded