Final answer:
To find the weight of 1200 bricks for a fireplace, calculate the volume of a single brick and multiply it by the number of bricks and weight of a cubic foot of bricks.
Step-by-step explanation:
To find the weight of the 1200 bricks needed to construct a fireplace, we first need to calculate the volume of a single brick. The dimensions of the brick are given as 10 inches by 2 1/2 inches by 4 inches. We can convert the dimensions to feet by dividing them by 12, so the dimensions become 10/12 feet by 2 1/2/12 feet by 4/12 feet.
Next, we find the volume of a single brick by multiplying the length, width, and height. In this case, it would be (10/12) * (2 1/2/12) * (4/12) cubic feet.
Finally, we multiply the volume of a single brick by the number of bricks needed, which is 1200. This gives us the total volume of the bricks needed. To find the weight, we multiply the total volume by the weight of a cubic foot of bricks, which is 95 pounds. So the weight of the 1200 bricks needed to construct a fireplace would be 1200 * [(10/12) * (2 1/2/12) * (4/12)] * 95 pounds.