Let Sam be (S+8) years while his sister is S years.
S(S+8) = 105
S^2+8S-105 = 0
(S+15)(S-7) = 0
Sam’s sister is 7 years and Sam is 15 years old.
Answer: One sample z test for means
Step-by-step explanation:
From the information given, the sample size is large. It is greater than 30. Again, the population standard deviation is given. This means that the test statistic would be the z score which is determined by the formula
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = population standard deviation
The probability value would be determined from the normal distribution table.
Therefore, the hypothesis test that should be used is
One sample z test for means
6/ sqrt(8)=
6/sqrt(8) * sqrt(8)/sqrt(8)
6sqrt(8)/8
3/4 * sqrt(8)
3/4 * sqrt(4*2)
3/4 * sqrt(4) * sqrt(2)
3/4 *2*sqrt(2)
3/2 *sqrt(2)
5/sqrt(11) *sqrt(11)/sqrt(11)
5sqrt(11)/11
5/11 *sqrt(11)
No. 0.70 is the same as 0.7, for the place value of 7 is the same for both (tenths place). In 0.70, the place value of 0 is the hundredth, which is not needed.
0.70 = 0.7
Disagree is your answer
hope this helps
