Question

the mid value of class interval is 42 and the class size is 10 find the lower and upper mark of the given interval

Answer 1

class size = 10
lower limit = 41
upper limit = 43
because 42 is the mid value of class interval.
lower mark = lower limit - m / 2
= 41/1 - 10 / 2
= 82 - 10 / 2 ( by taking lcm )
= 72 / 2
= 36
lower mark = 36

upper mark = upper limit - m / 2
= 43/1 - 10 /2
= 86 -10 / 2
= 76/2
= 38
upper mark = 38.