A builder is building 5 new homes. Each home has a foyer measuring 9 feet by 18 feet. Laminate flooring for each foyer costs $26.91 per square yard. What is the cost of the laminate floors for the foyers in all 5 homes?

$2421.90

Step-by-step explanation:

Since a yard is 3 feet, we can say the foyer is 3 yards by 6 yards (9 feet is 3 yards and 18 feet is 6). The area of a square is x*y, so the area of each floor is 3*6 = 18 square yards. Since there are 5 homes, there are 5 * 18 = 90 total square yards to laminate. That means that the total cost is 90 * 26.91 = $2421.90.

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents