How did you get 20% in the calculations?

Question

Mathematics

I was reading a book about Elon Musk and came across this paragraph:

How to make 10% profit? Minimize costs. Income minus expenses for the year is 10%. If at the same time using PayPal you pay 2% for your transactions, and using some other systems you pay 4%, then PayPal gives you a 20% increase in the profitability of your business. Only a complete fool would refuse such a thing, right?

I found it in the original, but the calculations are the same there:

When you look at like any given business, like say a business is making 10 percent profitability. They're making 10 percent profit when they may net out all of their costs. You know, revenue minus expenses in a year, they're 10 percent. If using PayPal means you pay 2 percent for your transactions and using some other systems means you pay 4 percent, that means using PayPal gives you a 20 percent increase in your profitability. You'd have to be brain dead not to do that. right?

How did it end up "increasing the profitability of your business by 20%"?

Answer 1

Using PayPal, you pay 2% instead of 4%, according to Musk.
That is, costs are reduced by 2% and these 2% go to profit.
Without PayPal profit 10%, with PayPal - 12%.
(12/10) * 100 = 120%, i.e. the percentage of profit grows by 20% (that is, 20 percent increase in profitability)

Answer 2

Clients pay Rs.
Your expenses:
PayPal - payments 8.82 rubles, commission 0.18 rubles, total 9 rubles, income 10-9 = 1 rubles.
Another bank - payments 8.82 rubles, commission 0.35 rubles, total 9.17 rubles, income 10-9.17 \u003d 0.83 rubles.
1 / 0.83 = 1.20, that is, the income when working through PayPal is 20% higher than through another bank.