Table 1 shows the marks obtained by 40 candidates in a test.

Given that the median mark is 35.5,
(a) find the value of x and y
(b) state the modal class
(c) calculate the standard deviation of the marks

Question

Table 1 shows the marks obtained by 40 candidates in a test.

Given that the median mark is 35.5,
(a) find the value of x and y
(b) state the modal class
(c) calculate the standard deviation of the marks

anonymous · Answer

|dw:1395904037444:dw|

anonymous · Answer

@zzr0ck3r can you help me with this ?

zzr0ck3r · Answer

I forgot stats, sorry. Its been to many years.

anonymous · Answer

oh gosh, really? hmm, it;s alright.. thank you anyway :))

ganeshie8 · Answer

Since there are a total of 40 candidates,
median = 20th + 21st / 2

anonymous · Answer

median = 20th + 21st / 2 
 I dont understand this

ganeshie8 · Answer

scratch that

ganeshie8 · Answer

4 + x + y + 10 + 8 = 40

x + y = 18

anonymous · Answer

Ok, I get the same too. but I make it x= 18 - y so I can use it later for substitute.
.

anonymous · Answer

or I shouldn't did that at the first place ?

ganeshie8 · Answer

not sure, sorry...

ganeshie8 · Answer

@eliassaab

anonymous · Answer

@richyw Can you help me?

richyw · Answer

I'm actually going to sleep now. hope you figure it out!

anonymous · Answer

@eliassaab i want your help for this question ...

cwrw238 · Answer

i'm struggling with this . i agree with whats stated already. I'm not sure if there's enough information given to solve this problem.

anonymous · Answer

@cwrw238 I already gave enough information for this question. I wrote exactly what was written in my book.