Something that we always go through in our life is the check of change, those little coins that the girl in the cafeteria passes us after we buy our lunch. Coins can be seen as money. "decimal", after all, they are worth less than grades like those of BRL 1.00.
An example of this is the way in which we represent the fifty cent coin (BRL 0.50), we can see that 0,50 it is a decimal number.
Therefore, to find out what change we will receive, we will have to carry out subtraction of decimal numbers.
Think about the following situation:
Peter It has BRL 4.00 to buy your lunch in your school cafeteria. He decided to buy a natural sandwich and an orange juice, which together total BRL 3.25. What should Peter's change be?
But see that the tenths also have nothing to lend to the hundredths. However, as they are very good friends, the tenths will go to the units see what they can achieve.
so we will take 1 unit and we'll lend to the tenths, but remember ...
So Peter's change will be R$0.75.
Calculate today what your change will be in the school canteen and see how interesting it is, after all, and if
deliver the wrong change? You have to know how to calculate it!
By Gabriel Alessandro de Oliveira
Graduated in Mathematics
Take the opportunity to check out our video lesson on the subject:
