Match the two columns
Column−IColumn−II(A) The class mark of the class interval(p) 13145−150 is(B) In a frequency distribution, the mid – value of a(q) 110class is 10 and width of each class is 6. The upperlimit of the class is(C) The mean of eight numbers is 40. If one(r) 22.5 – 27.5number is excluded, their mean becomes 30.The excluded number is(D) The class marks of a frequency distribution are(s) 147.515, 20, 25, 30,……The class corresponding to the classmark 25 is
Choose the correct option:
A-s; B-p; C-q; D-r
(A)→s;(B)→p;(C)→q;(D)→r
(A) Classmark
=145+1502=2952=147.5.
(B) Let the upper limit = x
Lower limit = y
∴x−y=6 and x+y2=10⇒x+y=20
On solving both the equations, we get x = 13 and y = 7
(C) Sum of the 8 observation =40×8=320
Sum of the 7 observation =30×7=210
Excluded observation is 320 - 210 = 110
(D) Class width = 20 - 15 = 5
Class mark = 25
∴ Required class,
(25−52)−(25+52)⇒22.5−27.5