Final answer:
To find the unit rate of production in marbles per minute, divide the total number of marbles produced by the number of minutes it took. In this case, the factory's unit rate of production is 25 marbles per minute.
Step-by-step explanation:
To find the unit rate of production in marbles per minute, we need to divide the total number of marbles produced by the number of minutes it took to produce them. In this case, the factory produced 4.5 x 104 marbles in 1,800 minutes. Dividing the total marbles by the total minutes gives us:
4.5 x 104 marbles / 1,800 minutes = 25 marbles/minute.
Therefore, the factory's unit rate of production is 25 marbles per minute, so the correct answer is option A.