Example: Find the mean of the following: 1, 2, 3, 4, 5 Step 1: Find the sum of all numbers → 1+2+3+4+5 = 15 Step 2: Divide total by the number of numbers → 15 ÷ 5 = 3
Example:
If 2n = 8, then n = ?
8
3
2
Example: 22
-22
>
=
<
Example:
What are the factors of 82?
2
9
41
28
Example:
PQ ∥ RS
FALSE
TRUE
Example:
Common multiples of 2 and 3
6, 12, 18,...
2, 3, 6, ...
6, 9, 12, ...
Example:
LCM (least common multiple) of 3 and 6
3
6
9
Example: 1, __ , 3, 4, 5; mean=3 Step 1: Let N be the missing number. Step 2: We know, Mean = (Sum of all numbers)/(Number of numbers); Therefore, Sum of all numbers = Mean x Number of numbers → 1 + N + 3 + 4 + 5 = 3 x 5 → N + 13 = 15 → N = 15-13 → N = 2