Answer:
11 hours she worked at the grocery store
Step-by-step explanation:
assuming,
the number of hours worked at tutoring = x
the number of hours worked at grocery store = y
which means,
the amount she made at tutoring = x* $15
the amount she made at grocery store = y*$9
we have 2 equations
<em>total number of hours</em>
1) x+y= 15
<em>total amount she earned</em>
2) x* $15+ y* $9= $159
From equation 1
x+y= 15
x=15-y
<em>we replace this x value in equation 2</em>
x* $15+ y* $9= $159
(15-y)* $15+ y* $9= $159
(15*15)- 15y+9y=159
225-6y=159
225-159=6y
66=6y
66/6=y
<u>11=y</u> <em>the number of hours she worked at grocery store. </em>
<em>we place y=11 in our derived x equation</em>
x=15-y
x=15-11
<u><em>x=4 </em></u><em>the number of hours she worked at tutoring. </em>
Answer:
The minimum sample size is 239.
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 Z-table as such z has a p-value of 
.
That is z with a pvalue of 
, so Z = 2.575.
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.
Population standard deviation is equal to 1.5
This means that 
Margin of error of 0.25
This means that 
What's the minimum size of the sample?
Rounding up:
The minimum sample size is 239.
Answer:
-13 is less than zero in the options
Answer:
no coco concho kicks sub chick lux 8jzjxjfxktx
