Three castings chosen from a batch of 145 weigh 5.34 kg, 5.38 kg, and 5.33 kg, respectively. Taking the average of these weights to be the average weight of the batch, find the cost of the batch at the rate of K7.17 per kg.

To find the cost of the batch, we first need to calculate the average weight of the castings. Then, we can multiply this average weight by the rate per kilogram to find the total cost.

Given:

Three castings with weights 5.34 kg, 5.38 kg, and 5.33 kg.
Rate per kilogram is K7.17.

First, let's calculate the average weight of the castings:

[tex]\[ \text{Average weight} = \frac{5.34 \text{ kg} + 5.38 \text{ kg} + 5.33 \text{ kg}}{3} \][/tex]
[tex]\[ \text{Average weight} = \frac{15.05 \text{ kg}}{3} \][/tex]
[tex]\[ \text{Average weight} = 5.0167 \text{ kg} \][/tex]

Now, we can calculate the total cost of the batch:

[tex]\[ \text{Total cost} = \text{Average weight} \times \text{Rate per kilogram} \][/tex]
[tex]\[ \text{Total cost} = 5.0167 \text{ kg} \times K7.17 \text{ per kg} \][/tex]
[tex]\[ \text{Total cost} \approx K1051.88 \][/tex]

Therefore, the cost of the batch at the rate of K7.17 per kg is approximately K1051.88.