b) 6) Simplify: a) 2(4-1)-(2- 3) + |1 -21. 4*-1 4*-2 x+1+1 Solve: c) 2 7 43x63 84x933 a) (2-x) = 27 b) x-1=15 The grades of grade 10 students in the midterm are distributed in the table below: Grades Incresing cumulative 3 10 10+ x 27 27+ y 39 42 frequencies 40 50 60 70 82 92 100 1-Determine x and y such that 12 is the increasing cumulative frequency of 60 and the frequency of grade 92 is 3. 2.- Suppose that x = 2 and y = 9. a) Draw the frequency table. b) Determine the population, the variable and its nature. c) Determine the mode and the median of this distribution. d) Calculate the mean x and the standard deviation o. e) Determine the percentage of students whose grades belong to the interval [x-0X +0].