X representa o numero das suas respostas certas.
y represnta o numero das suas respostas erradas.
O total de perguntas <span>é 25, portanto
x + y = 25
Agora tratamos do dinheiro.
Come</span>ça com <span>R$ 500,00
Pelas x respostas certas, recebe 200x.
Pelas y respostas errads perde 150y.
O total de dineheiro inicial mais os ganhos menos as perdas s</span>ão iguais a
R$ 600,00, portanto
500 + 200x - 150y = 600
200x - 150y = 100
20x - 15y = 10
Temos um sistema de duas equações com duas variaveis.
<span>x + y = 25</span>
20x - 15y = 10
15x + 15y = 375
+ 20x - 15y = 10
---------------------------
35x = 385
x = 11
x + y = 25
11 + y = 25
y = 14
Resposta: Errou 14 perguntas.
Answer:
1/3=33.33%?
Step-by-step explanation:
the only math I see is 1/3 and a random 0 near O's
Answer:
Sensory adaptation? im guessing
Step-by-step explanation:
Make 37.5% into decimal form : Since it is being marked up, add 100% = 1.375
1.375 x 80
1.375
x 80
_________
0000
+11000
_________
110.000
80 marked up by 37.5% is 110.
Answer:
x = 7
Step-by-step explanation:
Rule: an even number of - signs written one after another produces a plus number.
So - - 3 = 3
The rule also lets you do something strange like
- - - - 4 = 4 but you hardly ever see this.
Rule: an odd number of minus signs produces a minus number.
x + 3 = 10 Subtract 3 from both sides.
x + 3 - 3 = 10 - 3
x = 7