To find the total number of nails the hardware store ordered, you need to multiply the number of packs by the number of nails in each pack.
The calculation is as follows:
\[ \text{Total nails} = \text{Number of packs} \times \text{Nails per pack} \] \[ \text{Total nails} = 15 \times 145 \]
Now, let's perform the multiplication:
\[ 15 \times 145 = 2175 \]
Therefore, the hardware store ordered 2175 nails.