All Junior Cert Mathematics posts
• #### mid-intervals Sarah2014

im doing the 2015 paper 2 q 9 can someone explain how I get the mid-interval (estimate the mean number)? thanks

1. #### Jack_Davis15

wheres sryanbruen when u need him

2. #### Sarah2014

I know haha :):) wheres he gone !!

3. #### JackW

Mid intervals is where you find halfway between the two numbers that bound the data values.i.e. With 0 & 30 the mid interval is (0+30)/2=15. You then just assume that everyone who got between 0 & 30 got 15 to find the mean

4. #### Study2000

Mid-interval Answer: (1)(15)+(2)(40)+(10)(60)+(7)(85)+(5)(130) and then u divide this by (1+2+10+7+5).. and u should get 77.6 as ur answer!

5. #### Study2000

all u do for this question is that u find the halfway between the two number and multiply the number u found by the number of students.

Example: step1:(0-30)

step2:(to find halfway add two numbers and divide by 2). (u get 15)

step3:(multiply 15 by number of students which is 1 in this case)

6. #### SryanBruen

I'm right here... a bit late LOL

7. #### Sarah2014

thanks guys