Final answer:
The hardware store now keeps an inventory of 199,749 lawnmowers.
Step-by-step explanation:
To find out how many lawnmowers the hardware store keeps now, we need to calculate 10% of the original inventory and add it to the original inventory. First, we find 10% of 181,590 by multiplying it with 0.10, which gives us 18,159. Then, we add this amount to the original inventory: 181,590 + 18,159 = 199,749. Therefore, the hardware store now keeps an inventory of 199,749 lawnmowers.