The mode is easy and I remember it using MOst (The MO meaning Most Often). In your exam, you will probably be given a set of numbers -
Before you can attempt averages, you need to put these numbers in numerical order - 1,4,6,7,9,9,9,9,11,12,15,19,22,23,25.
Just find the number that is repeated in the sequence most often (in this case 9) and your sorted. Easy.
Median is just the middle number of a sequence. I'll use the same set of numbers (minus the numerical order bit):
The median is basically what it says on the tin - the middle number and the easiest way of doing that is to cross the numbers out one by one;
1 then 15 then 4 then 23 and so on until you get something like this :
1,4,6,7,9,9,9,9, 11,12,15,19,22,23,25. The median is 9.
The mean is so easy, a five year old could do it (providing they can add and divide). Again, I'll use the same set of numbers: 1,4,6,7,9,9,9,9,11,12,15,19,22,23,25.
All you do is add em' up 1+4+6+7+9+9+9+9+11+12+15+19+22+23+25=181 (you may need a calculator) and divide by how many numbers there are (15)
The numbers on your exam will add up to make a whole number/ integer.
Same set of numbers again -
Smallest > 1,4,6,7,9,9,9,9,11,12,15,19,22,23,25 < Biggest
The range is probably the easiest of all the averages. You just take the smallest number away from the biggest: 25 - 1 = 24 < thats the range.
I hope my average revision cards helped, they're my first set so let me off with a few mistakes! Thanks.