permutation and combination Question no. 31 In a plane , there are 10 points out of which 4 are collinear , then the number of triangles that can be formed by joining these points are looks_one 60 looks_two 116 looks_3 120 looks_4 None of these Answer Option looks_two 116 Solution Solution : No. of triangles = n C 3 - p C 3 = 10 C 3 - 4 C 3 = 120 - 4 = 116 Question no. 32 The number of straight lines joining 8 points on a circle is looks_one 8 looks_two 16 looks_3 24 looks_4 28 Answer Option looks_4 28 Solution Solution : No. of straight line = n(n-1)/2 = 8 *7 / 2 = 28 Question no. 33 The number of diagonals in a polygon of m sides is looks_one m(m-5)/2! looks_two m(m-1)/2! looks_3 m(m-3)/2! looks_4 m(m-2)/2! Answer Option looks_3 m(m-3)/2! Solution Solution : The number of diagonals in a polygon of m sides is m(m-3)/2! Question no. 34 How many ...

permutation and combination Question no. 1 how many words can be formed using all the letters pf the words 'NATION' so that all the three vowels should never come together? looks_one 354 looks_two 348 looks_3 288 looks_4 None of these Answer Option looks_3 288 Solution Solution : No. of ways so that all the three vowels should never come together = Total of ways - No. of ways so that all the three vowels should come together = 6!/2! - 3! * 3! * 2 = 288 Question no. 2 In how many ways can the letters of the words 'GLOOMY' be arranged so that the two O's should not be together ? looks_one 240 looks_two 480 looks_3 600 looks_4 720 Answer Option looks_one 240 Solution Solution : Total number of ways so that the two O's should not be together = total no. of ways - no. of ways two O's should be together = 6!/2! - 5 * 4! = 240 Question no. 3 If P(77,31) = x and C(...