Answer:
A 90% confidence interval for the mean number of letter sounds identified in one minute is: (30.84, 37.34).
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
That is z with a pvalue of 
, so Z = 1.645.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 34.09 - 3.25 = 30.84.
The upper end of the interval is the sample mean added to M. So it is 34.09 + 3.25 = 37.34.
A 90% confidence interval for the mean number of letter sounds identified in one minute is: (30.84, 37.34).
Answer:
35
Step-by-step explanation:
all are obeying a constant ratio
- copper 81
- tin 14⇒?
- lead 5
- total 100 ⇒250
- ?=250*14/100=35
Answer:
77 Sq m
Step-by-step explanation:
Area of the shaded shape = Area of the rectangle with dimensions 14 m by 8m - Area of rectangle with dimensions ( 14 - 5 - 2=7) 7m by 5m.
= 14*8 - 7*5
= 112 - 35
= 77 Sq m
Answer:
x = 10
Step-by-step explanation:
it has 8 sides so:
total interior angle degrees = (180° x 8 sides) - 360° = 1080°
11x + 14 + 4x + 87 +2x + 70 + 4x + 31 + x + 92 + 3x + 167 + 5x + 48 + 2x + 251 = 1080°
combine like terms:
32x + 760° = 1080°
subtract 760° from both sides of the equation:
32x = 320°
divide both sides by 32:
x = 10
Answer:
add the negative to the 0 that is left alone at the end then carry the x2 over to the side bringing it down with the x and cancel them taking away the 2. the answer is -1
Step-by-step explanation:
