Answer:
205.81 to 214.19
Step-by-step explanation:
Sample size (n) = 50
Sample mean weight (X) = 210 grams
Sample standard deviation (s) = 18 grams
Confidence coefficient (Z) at 90% = 1.645
The confidence interval for the true mean breaking strength of cotton threads of this type, at a 90% confidence level, is given by:

The confidence interval is 205.81 grams to 214.19 grams.
The applicable formula is
A = P(r/12)/(1 -(1+r/12)^(-12n))
where P is the principal amount,
r is the annual interest rate (compounded monthly), and
n is the number of years.
Using the formula, we find
A = 84,400*(0.04884/12)/(1 -(1+0.04884/12)^(-12*15))
= 84,400*0.00407/(1 -1.00407^-180)
= 343.508/0.518627
≈ 662.34
The monthly payment on a mortgage of $84,400 for 15 years at 4.884% will be
$662.34
Answer:
0.75 or 3/4
Step-by-step explanation:
1/4 of 3 would still end up to be 3/4 or as a decimal it would be .75