Equal percentage increases and decreases do not cancel. The resulting change, (1-p)(p+1) , is always less than the initial value. For example, if you make 50% on an investment and then lose 50%, the result is a loss of 25%: (1+1/2)(1-1/2) = 3/4 . Going the other way, to make up for a loss of 50%, you need to make 100%, not just 50%Componente Curricular::Ensino Médio::Matemática