Question

Tamara has three rows of two $6$ -feet by $2$ -feet flower beds in her garden. The beds are separated and also surrounded by $1$ -foot-wide walkways, as shown on the diagram. What is the total area of the walkways, in square feet?

$72$

$78$

$90$

$120$

$150$

Answer: B

Concepts:area decomposition rectangle

Difficulty rating: 960

Solution:

We can see that the width of the garden is $2 \cdot 6 + 3 \cdot 1 = 15.$ We can also see that the height is $3 \cdot 2 + 4 \cdot 1 = 10.$ The total area of the garden is therefore $15 \cdot 10 = 150.$ The area of all the flower beds is $6 \cdot 2 \cdot 6 = 72.$ Subtracting this from the area of the garden yields $150 - 72 = 78,$ which is the area of the walkways.

Thus, B is the correct answer.

2017 AMC 10A Problem 3

Answer: B

Difficulty rating: 960

Solution:

Problem 3 in Other Years