Question

Brooke has set up 70 chairs in equal rows for the class talent show. But,there is not room for more than 20 rows. What are the possible number of rooms that Brooke could set up?

Mathematics ​

Answer 1

Answer: If the rows must be even, she can set

14 rows of 5 chairs

10 rows of 7 chairs

7 rows of 10 chairs or

5 rows of 14 chairs

Explanation:

Take the prime factors of 70: 2, 5 and 7 Multiply them in different ways to get the combinations where no product is greater than 20. (7 ×5 is the one combination of factors that won't work)