Question

A store normally sells windows at $\$100$ each. This week the store is offering one free window for each purchase of four. Dave needs seven windows and Doug needs eight windows. How many dollars will they save if they purchase the windows together rather than separately?

$100$

$200$

$300$

$400$

$500$

Answer: A

Concepts:money basic counting

Difficulty rating: 1170

Solution:

Alone, Dave pays for $6$ windows and receives one free to reach $7,$ costing $\$600;$ Doug pays for $7$ and receives one free to reach $8,$ costing $\$700.$ Separately they pay $\$1300.$ Together they need $15$ windows: buying $12$ yields $3$ free, for $\$1200.$ The savings are $1300 - 1200 = 100$ dollars.

Thus, the correct answer is A.

2005 AMC 10A Problem 5

Answer: A

Difficulty rating: 1170

Solution:

Problem 5 in Other Years