IBMediumStatistics10–12

Test scores follow $N\left(50, 10^{2}\right)$ and $2500$ students sat the test. Given that $P(Z > 1.5) = 0.0668$ , how many students, to the nearest student, scored above $65$ ?

As pontuações de um teste seguem $N\left(50, 10^{2}\right)$ e $2500$ alunos realizaram o teste. Sabendo que $P(Z > 1{,}5) = 0{,}0668$ , quantos alunos, com arredondamento à unidade, tiveram mais de $65$ pontos?

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Solution

Step 1 of 3

1.Standardise: $z = \frac{65 - 50}{10} = 1.5$

Test scores follow N(50,102)N\left(50, 10^{2}\right)N(50,102) and 250025002500 students sat the test. Given that P(Z>1.5)=0.0668P(Z > 1.5) = 0.0668P(Z>1.5)=0.0668, how many students, to the nearest student, scored above 656565?

Answer options

Test scores follow $N\left(50, 10^{2}\right)$ and $2500$ students sat the test. Given that $P(Z > 1.5) = 0.0668$ , how many students, to the nearest student, scored above $65$ ?