Can you explain how to solve this math problem: Bob is building a garden on his land, and he wants it to be fenced in to keep out varmints. The garden is a rectangular plot 225 feet long by 125 feet wide. He also wants to have a small 3-foot wide gate to walk through and a larger 10-foot wide gate to move his gardening equipment through. How much fencing is Bob going to need to fence in his garden, taking into account the two gates?