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4. link:http://img528.imageshack.us/img528/8664/dsc00253ra5.jpgThe dartboard shown in the figure is divided into 35 equal divisions. Landing in regions A, B, C and D gets 4, 3, 2 and 1 points respectively. A dart is thrown and hits the dartboard.(a) Find the probability taht it lands in one of the following... 顯示更多 4. link:http://img528.imageshack.us/img528/8664/dsc00253ra5.jpg The dartboard shown in the figure is divided into 35 equal divisions. Landing in regions A, B, C and D gets 4, 3, 2 and 1 points respectively. A dart is thrown and hits the dartboard. (a) Find the probability taht it lands in one of the following regions: (i) redion A (ii) region D (b) Find the expected score, correct to 2 decimal places.[Assume the dart doesn't land in the boundaries.] 5. If the mean of three numbers is 13 and the mean of another five numbers is 19, find the mean of the eight numbers. 6.Given the set of data: x/2, 4x/5, 6x/7, x/3, 7x/6 Find the value of x when the median is 8. 更新: 2. How many km is it between two places, if a car travelling 2d km an hour takes 3 hours to finish the journet
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4. Among the 35 divisions: No. of divisions of Region A = 1 No. of divisions of Region B = 2 No. of divisions of Region C = 3 No. of divisions of Region D = 8 No. of division of other region = 21 (a) (i) Probability that the dart lands in region A = 1/35 (ii) Probability that the dart lands in region D = 8/35 (b) Expected score = (1/35)x4 + (2/35)x3 + (3/35)x3 + (8/35)x3 Expected score = (4/35) + (6/35) + (9/35) + (24/35) Expected score = 43/35 Expected score = 1.23 (to 2 decimal places) ===== 5. Sum of the three numbers with sum 13 = 13x3 Sum of the five numbers with sum 19 = 19x5 Mean of the eight numbers = (Sum of the eight numbers) / 8 Mean of the eight numbers = (13x3 + 19x5) / 8 Mean of the eight numbers = 16.75 ===== 6. Arrange the data in ascending order : x/3, x/2, 4x/5, 6x/7, 7x/6 The median: 4x/5 = 8 Hence, x = 10 ===== 2. Speed = 2d km/h Time = 3 h Distance = Speed x time Distance = (2d km/h) x (3 h) Distance = 6d km =
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