Question (b)(ii) and (b)(iii) thanks!!

The following table shows the ages of a certain number of interviewees participated in a survey and X , the number of yogurt parfait cups they eat in a particular month: Number of yogurt parfait cups ate Is X s10 11 s X s 20 21 S X s 30 Total 18 or below 50 75 125 250 18 to 40 70 65 15 150 Age 41 to 60 55 10 5 70 61 or above 25 4 a Total 200 154 b n - For the number of yogurt parfait cups eaten, write down (i) the class mark of the class 21s X s 30; 25. 5 (ii) the upper class boundary of the class Is X s 10; 10 . 5 (iii) the modal class. 1 2 X