-6 points
But it’s definitely not 30% worth of additional value.
They’re actually claiming to be adding almost 50% (43%, to be precise) in value, since that’s how much more you have to add to end up at 30% of the final value. (By analogy, imagine they took a 50% cut. That would be claiming to double the value. Something that used to be worth $10 is now going to cost $20 if the original wants to maintain the same cut.)