A national survey shows that $$$95 \%$$$ of year 12 students use social media. Arvin suspects that the percentage of year 12 students at his college who use social media is less than the national percentage. He chooses a random sample of 20 students at his college and notes the number who use social media. He then carries out a test at the $$$2 \%$$$ significance level. Find the rejection region for the test. ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................

Mathematics

IGCSE&ALevel

CAIE

Exam No：9709_m20_qp_62 Year：2020 Question No：7(a)

Answer:

$\mathrm{P}(X \leqslant n) \quad(n \leqslant 20)$ attempted, using $\mathrm{B}(20,0.95)$
$\mathrm{P}(X \leqslant 17)$ or $\mathrm{P}(X \leqslant 16)$ attempted, using $\mathrm{B}(20,0.95)$
$(\mathrm{P}(X \leqslant 17))=0.0755$ and $(\mathrm{P}(X \leqslant 16))=0.0159$
Rej region is $X \leqslant 16$ or $\mathrm{X}<17$

Answer:

Knowledge points:

Solution:

Answer:

Knowledge points:

Solution:

Related Question