Answer: a) (1008.34,1019.658) b) (1009.24,1018.76)
Step-by-step explanation:
Since we have given that
n = 75
mean = 1014 hours
Standard deviation = 25 hours
At 95% two sided , z = 1.96
So, confidence interval would be
(b) Construct a 95% lower confidence bound on the mean life.
z = 1.65
So, confidence interval would be
Hence, a) (1008.34,1019.658) b) (1009.24,1018.76)
Let the youngest sister be n years
Lana will be 2n years, as her youngest sister is half her age
The age of the twins separately will be 2n-2 as they are 2 years younger than Lana
So, the equation looks like this:
n + 2n + 2(2n-2) = 45
Now solve for n:
3n + 4n - 4 = 45
7n - 4 = 45
7n = 49
n = 7
So the youngest sister is 7, Lana is 14 and the twins are 12. 14 + 12 + 12 + 7 =45
90% out of 105% which would be 0.85
If you know the definition of expand (to increase or make bigger)
then this will be easy.
when ever it asks for expanded for that means your answer has to be bigger than the number your given.
for your question:
you have 7,080,267
so u first do the biggest value which is the first 7 on the left.
and then work your way down to the smallest which would be 7 on the right.
7000000
000000
80000
0000
200
60
7
that is the numbers expanded
but now u have to write it in the fom so you just add a + after each number
7000000+000000+80000+0000+200+60+7
you can shorten it by removing the numbers with no value:
7000000+80000+200+60+7