Answer:
340 phones
Step-by-step explanation:
Make an expression
She repairs 10 phones each day, d.
Each day she repairs 10 phones, it is 10 phones off the total number (450) she has to repair, so we can subtract 10d from 450.
450-10d
We want to find how many she has left after 11 days, so we can substitute 11 in for d
450-10(11)
Multiply
450-110
340
She will still have 340 phones left to repair
Answer:
946
Step-by-step explanation:
Let's make an equation :
34% of x = 321.8
Covert 34% into decimal by dividing by 100 :
34 ÷ 100 = 0.34
Rewrite equation with decimal form :
0.34x = 321.8
Divide both sides by x to make x the subject :
x = 321.8 ÷0.34
x = 946.470588235
To the nearest whole number will be 946 as 4 rounds it down
So our final answer will be 946
Hope this helped and have a good day
Answer:
The 90% confidence interval for the mean time required by all college graduates is between 5.36 years and 5.44 years.
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 
.
So it is z with a pvalue of 
, so 
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 5.4 - 0.04 = 5.36 years.
The upper end of the interval is the sample mean added to M. So it is 5.4 + 0.04 = 5.44 years.
The 90% confidence interval for the mean time required by all college graduates is between 5.36 years and 5.44 years.
