Question

Suppose we have a binomial experiment in which success is defined to be a particular quality or attribute that interests us.

(a)

• Suppose n = 43 and
• p = 0.26.

(For each answer, enter a number. Use 2 decimal places.)
n·p =
n·q =

Can we approximate p̂ by a normal distribution? Why? (Fill in the blank. There are four answer blanks. A blank is represented by _____.)

_____, p̂ _____ be approximated by a normal random variable because _____ _____.

first blank

YesNo    

second blank

cancannot    

third blank

n·p does not exceedn·q exceeds    n·q does not exceedn·p exceedsboth n·p and n·q exceedn·p and n·q do not exceed

fourth blank (Enter an exact number.)


What are the values of μ_p̂ and σ_p̂? (For each answer, enter a number. Use 3 decimal places.)
μ_p̂ = mu sub p hat =

σ_p̂ = sigma sub p hat =

(b)

Suppose

• n = 25 and
• p = 0.15.

Can we safely approximate p̂ by a normal distribution? Why or why not? (Fill in the blank. There are four answer blanks. A blank is represented by _____.)

_____, p̂ _____ be approximated by a normal random variable because _____ _____.

first blank

YesNo    

second blank

cancannot    

third blank

n·p does not exceedn·q exceeds    n·q does not exceedn·p exceedsboth n·p and n·q exceedn·p and n·q do not exceed

fourth blank (Enter an exact number.)

(c)

Suppose

• n = 61 and
• p = 0.18.

(For each answer, enter a number. Use 2 decimal places.)
n·p =
n·q =

Can we approximate p̂ by a normal distribution? Why? (Fill in the blank. There are four answer blanks. A blank is represented by _____.)

_____, p̂ _____ be approximated by a normal random variable because _____ _____.

first blank

YesNo    

second blank

cancannot    

third blank

n·p does not exceedn·q exceeds    n·q does not exceedn·p exceedsboth n·p and n·q exceedn·p and n·q do not exceed

fourth blank (Enter an exact number.)


What are the values of μ_p̂ and σ_p̂? (For each answer, enter a number. Use 3 decimal places.)
μ_p̂ = mu sub p hat =

σ_p̂ = sigma sub p hat =

Answer 1

a) n·p =43*0.26=11.18
n·q =43*(1-0.26)=31.82

Yes, p̂ can be approximated by a normal random variable because both n·p and n·q exceed 10.


What are the values of μp̂ and σp̂? (For each answer, enter a number. Use 3 decimal places.)
μp̂ = mu sub p hat =0.26

σp̂ = sigma sub p hat =

(b)

np=25*0.15=3.75<10

No, p̂ can not be approximated by a normal random variable because n·p does not exceed 10.

(c)

np =61*0.18=10.98

nq=61*(1-0.18)= 50.02

Yes, p̂ can be approximated by a normal random variable because both n·p and n·q exceed 10.

Use 3 decimal places.)
μp̂ = mu sub p hat =0.18

σp̂ = sigma sub p hat =