The Paleozoic Era lasted approximately 299 million years, while the Mesozoic Era lasted approximately 186 million years.

To find out how many times longer the Paleozoic Era was, we can divide the length of the Paleozoic by the length of the Mesozoic:

299 million years / 186 million years ≈ 1.61 times longer

Therefore, the Paleozoic Era was about 1.61 times longer than the Mesozoic Era.