How can something be greater than $100\%$?

Apologies, my mathematics is poor but I saw an advert recently which said:

Up to $350\%$ more likely to quit

How can something be greater than $100\%$? It can't be can it?


Solution 1:

Say 1 out of 10 people quit in year 1. Now if 4.5 out of 10 people quit in year 2 it is up 350%. Does this make sense? The percentages compare numbers relative to each other.

Solution 2:

$100$% of something means all of it.

$200$% of the same thing means twice as much.

$350$% means $3.5$ times the original amount.