Final answer:
The smallest dollar amount for which Jenny and Trey sold the same amount is $12.
Step-by-step explanation:
To find the smallest dollar amount for which Jenny and Trey sold the same amount, we need to find a common multiple of $4 and $6.The question revolves around finding the smallest dollar amount for which Jenny and Trey can sell the same dollar amount of cookies at different prices per box. To determine this amount, we must find the least common multiple (LCM) of the two prices, $4 and $6. The multiples of $4 are 4, 8, 12, 16, 20, 24,..., and the multiples of $6 are 6, 12, 18, 24, 30,.... The smallest common multiple they share is $12. Therefore, Jenny can sell 3 boxes at $4 each to make $12, and Trey can sell 2 boxes at $6 each to also make $12.
The multiples of $4 are $4, $8, $12, $16, $20, $24, $28, ...
The multiples of $6 are $6, $12, $18, $24, $30, $36, ...
The smallest common multiple between $4 and $6 is $12. Therefore, the answer is a) $12.