Answer: 8359
Step-by-step explanation:
The formula for sample size needed for interval estimate of population proportion :-
Given : The significance level :
Critical value :
Previous estimate of proportion :
Margin of error :
Now, the required sample size will be :-
Hence, the required sample size = 8359
Answer:
2 lbs 9 oz
Step-by-step explanation:
Lets line up the ounces and pounds and subtract
5 lb. 10 oz.
− 3 lb. 1 oz.
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2 lbs 9 oz
Answer: 35 additional teachers are needed
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Explanation:
We have 2470 students and the ratio of students to teachers is 26:1. This means that for every teacher, there are 26 students. Put another way, we can set up this ratio
2470/x = 26/1
where x is the number of teachers. Cross multiply and solve for x
2470/x = 26/1
2470*1 = 26*x
2470 = 26x
26x = 2470
26x/26 = 2470/26
x = 95
So we have 95 teachers currently
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Let y be the new number of teachers needed to bring the ratio down to 19:1
Using a similar idea as done above, we would have this ratio
2470/y = 19/1
Let's solve for y
2470/y = 19/1
2470*1 = 19*y
2470 = 19y
19y = 2470
19y/19 = 2470/19
y = 130
So we'll need 130 teachers to have the ratio be 19:1
The difference of the values is y - x = 130 - 95 = 35, which is the final answer. This is the additional amount of teachers needed.