Proportionality. Rule of three. First degree equations

Area : Math. Type : Individual. Level : First cycle of ESO.

• The social and democratic state of law has one objective: that all citizens can live as well as possible. To achieve this, it offers services that must be paid for by everyone: If, for example, 7% is spent on education, how much has been invested if the expected revenue of €927,494.47 million is expected in 2023? How much would be allocated to education if the investment were 9%?

• Calculate how much the State spends per student using the result of the previous problem and knowing that there are 250,000 students.

• Is the relationship between the number of students and the State's financial investment directly or indirectly proportional?

• Indicate which of these magnitudes are directly proportional and which are not:

  • What a citizen receives for his work and the taxes he must pay.

  • The number of children a taxpayer has and the taxes they must pay.