Example: Find the mode of the following: 1, 2, 4, 5, 5
Step 1: Sort the list → 1, 2, 4, 5, 5
Step 2: Find the number that is repeated the most number of times.
Step 3: In the above list, 5 is repeated twice and all the other numbers occur only once. Therefore, the mode is 5.

Example: Lucy had 1 blue, 3 green and 4 red pens. What type of a ratio is 3:4??

Example: Find the median of the following: 1, 2, 1, 5, 5
Step 1: Sort the list → 1, 1, 2, 5, 5
Step 2: Count of numbers listed → 5 (odd)
Step 3: So the middle number is (count+1)/2 → (5+1)/2 → 3^rd number. Therefore, the median is 2.

Example: What is the area of a circle whose diameter is 10 cm?
Given: Diameter(d) = 10cm; So, Radius(r) = Diameter/2 = 10/2 = 5cm
Area of a circle: πr² = π x 5² = π x 25 = 25π sq cm

Example: What is the area of a circle whose radius is 5 cm?
Given: Radius(r) = 5 cm
Area of a circle: πr² = π x 5² = π x 25 = 25π sq cm

Example: Rails in a railway track