Answer:
Step-by-step explanation:
Given that IQ mean is 100 and std dev = 12 for normal adults

Std error = 

i.e. sample size should be atleast 97
The required sample size is 97.
This is reasonable as this is greater than 30
Yes. This number of IQ test scores is a fairly large number.
Answer:
12k+3n
Step-by-step explanation:
Answer:
Perimeter: 24
Area: 1105.92
Step-by-step explanation:
Perimeter:
Add up all of the numbers
Area:
Multiply all of the numbers
(I'll redo it if this isn'twhat you meant by)
Answer:
15 hours
Step-by-step explanation:
9 lawns is 3 times as much as 3 lawns
it will take 3 times as long
3 * 5 hours = 15 hours