There are 1,154 souvenir paperweights that need to be packed in boxes. Each box

Total mean= 27cm

Total standard deviation = 0.1849mm

Step-by-step explanation:

The mechanical assembly has three parts consisting of the length of the rod (the this be called x), the length of the bearing (be called y). You might be wondering where the third part is but the assembly usually has two bearings. Then the second length of the bearing (be called z).

From the problem,

μx = 23, μy =2, μz = 2

σx = 0.18, σy = 0.03, σz = 0.03

We can find the total Mean by adding all the means,

μxyz =  23 + 2 + 2 = 27cm

Since the length of the assembly are independent,

To find the total standard deviation, we must first find the total variance(square of standard deviation)

σ² = (0.18)² + (0.03)² + (0.03)² =  0.0342

Now, we find the standard deviation (square root of the variance)

σ = √0.0342 = 0.18493242

σ ≈ 0.1849mm (you can change to cm by multiplying by 10)