To find the number of stamps on the poster, we need to calculate the total area of the poster board and then divide it by the area of each stamp.
Given:
Poster board dimensions: 2 1/2 ft by 1 ft
Stamp size: 2 in by 2 in
First, we need to convert the measurements to a common unit. Let's convert everything to inches since the stamp size is given in inches.
1 ft = 12 inches (since 1 foot = 12 inches)
2 1/2 ft = 2 ft + 1/2 ft = 24 inches + 6 inches = 30 inches
Now, we can calculate the area of the poster board:
Area of poster board = Length × Width = 30 inches × 12 inches = 360 square inches
Next, we find the area of each stamp:
Area of each stamp = Length × Width = 2 inches × 2 inches = 4 square inches
Now, we can find the number of stamps on the poster by dividing the total area of the poster board by the area of each stamp:
Number of stamps = Total area of poster board ÷ Area of each stamp = 360 square inches ÷ 4 square inches = 90 stamps
Therefore, there are 90 stamps on the poster.
The correct answer is:
B) 90