BITSAT2009MathematicsFunctionsActual
Given below is a frequency distribution with median 46 . In this distribution, some of the frequencies are missing : Determine the missing frequencies. ( array |c|c|c|c|c|c|c|c|c| Marks & 10-20 & 20-30 & 30-40 & 40-50 & 50-60 & 60-70 & 70-80 & Total No. of students & 12 & 30 & ? & 65 & ? & 25 & 18 & 229 array )
Options
- A34,45
- B25,40
- C12,18
- D30,35
Correct answer
A. 34,45
Step-by-step solution
( array |c|c|c| Marks & No. of s tudents & c.f. 10-20 & 12 & 12 20-30 & 30 & 42 30-40 & ? & 42+ x 40-50 & 65 & 107+ x 50-60 & ? & 107+ x + y 60-70 & 25 & 132+ x + y 70-80 & 18 & 150+ x + y Total & 229 & array ) ( aligned & n 2 = 229 2 =114.5, Median =46 & Median class =40-50 & =40, c.f. =42+ x , f =65, ~h =10 & Median = + ( n 2 - c.f. f ) h & 46=40+ 114.5-(42+ x ) 65 10 & or 46-40= (114.5-42- x ) 13 2 & 6= (72.5- x ) 13 2 or 78=145-2 x & 2 x =145-78=67 or x = 67 2 =33.5 aligned ) ( x =34( ) Number of students canno