Why are decimals used to represent clock time?
The use of time in decimals occurs a lot in the personnel department area, which is the area within companies responsible for carrying out calculations for paying employees.
Use is due to the fact that payments are made in currency, so think about this scenario:
João is paid for hours worked, his hour costs R$ 25.00, during the calculation period for payment the PD calculated a total of 07:34 (seven hours and thirty-four minutes).
Quick thinking would tell us to do a basic multiplication, 25 x 7.34, resulting in the value of R$ 183.50, but this calculation is wrong!
The unit of measure of time goes from 0 to 60, since the only currency is from 0 to 100, so note that there is no way to compare 0 to 60 with 0 to 100, and that's where the decimal comes in.
As we have already seen that to convert minutes into decimals just divide them, we have:
34 (the 34 minutes worked) / 60, which is exactly 0.5666666667.
Before carrying out the calculation, an explanation is in order, mathematics advises us that from 5 rounding is applied, so our 0.56 must be 0.57, however you will find situations in which rounding is not used.
But following the calculation, 34 minutes in decimals corresponds to 0.57 in centesimals, so:
BRL 25.00 x 7.57 = BRL 189.25, so we conclude that João will receive BRL 189.25 for the 07:34 worked.
See that when we calculate with minutes the result was lower, this is precisely because minutes go up to 60, and currency up to 100, as the payment is in currency, the conversion is applied before discovering the amount to be paid.
