@sherwinsayo420 Well, I suppose there are units of penny, if you see the minimal unit is the penny which is numbered has “1” then ONE HUNDRED will bee 100 pennies multiplied by one hundres (100), that will be 10000 pennies, equally with the TWENTY, that will be 100 pennies multiplied by 20 that has as a result 2000 units of pennies.
In this solution, the coder has decided to make their monetary units cents instead of dollars. This allows them to work in whole numbers and avoid problems with floating point precision.