Are there 5 epochs?

No, 120.Or, 5x5-5+5-5 = 20

If you times 5 5 5 5 that would make 20 and another 5 you get twenty five it's dead simple it's in your five times table so do 5 times 5 = 25 there you have it

(5 * 5) - ((5/5)5) = 25 - 1 = 24.

5x5+5-5+5=30 Steps Broken down 5x5=25 25+5=30 30-5+25 25+5+30

5+5+5+5=20