In the first three papers each of 100 marks, Ahmad got 90,77,83 marks. If he wants an average of greater than 75 marks and less than 80 marks, find the range of marks he should scored in 4th paper. A. 50 < X < 70
B. 75 < X < 80
C. 73 < X < 100
D. 25 < X < 75

The price of an item has been reduced by 30%. the original price was $30. what is the price of the item now ?

Points a, b, and c form a triangle. complete the statements to prove that the sum of the interior angles of triangle abc is 180

3.17 scores on stats final. below are final exam scores of 20 introductory statistics students. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 57, 66, 69, 71, 72, 73, 74, 77, 78, 78, 79, 79, 81, 81, 82, 83, 83, 88, 89, 94 (a) the mean score is 77.7 points. with a standard deviation of 8.44 points. use this information to determine if the scores approximately follow the 68-95-99.7% rule. (b) do these data appear to follow a normal distribution? explain your reasoning using the graphs provided below.