REI recently changed its return policy on hiking boots from exchanging boots after any time period to only exchanging in the first 24 months, because too many hikers were not returning the boots because of problems, but because they had worn out. REI wants to know how long hiking boots last on average. A shoe materials specialist said that shoes worn regularly wear out with a standard deviation of 7.4 months. If REI wanted to calculate a 95% confidence interval for the number of days that hiking boots last with a margin of error of ±1 month, how large a sample size would REI need to take?

$\frac{20b}{{\left(4b^3\right)}^3}$

Which operation could we perform in order to find the number of milliseconds in a year??
${\displaystyle 60\cdot 60\cdot 24\cdot 7\cdot 365}$
${\displaystyle 1000\cdot 60\cdot 60\cdot 24\cdot 365}$
${\displaystyle 24\cdot 60\cdot 100\cdot 7\cdot 52}$
${\displaystyle 1000\cdot 60\cdot 24\cdot 7\cdot 52?}$

Tell about the meaning of Sxx and Sxy in simple linear regression,, especially the meaning of those formulas

Is the number 7356 divisible by 12? Also find the remainder.
A) No
B) 0
C) Yes
D) 6

What is a positive integer?

Determine the value of k if the remainder is 3 given ${\displaystyle (x^3+k{x}^2+x+5)÷(x+2)}$

Is $41$ a prime number?

What is the square root of $98$?

Is the sum of two prime numbers is always even?

149600000000 is equal to
A)$1.496\times <!--\; \times \; -->{10}^{11}$
B)$1.496\times <!--\; \times \; -->{10}^{10}$
C)$1.496\times <!--\; \times \; -->{10}^{12}$
D)$1.496\times <!--\; \times \; -->{10}^8$

Find the value of$\log 1$ to the base $3$ ?

What is the square root of 3 divided by 2 .

write ${\displaystyle \sqrt[5]{{\left(7x\right)}^4}}$ as an equivalent expression using a fractional exponent.

simplify ${\displaystyle \sqrt{125n}}$

What is the square root of ${\displaystyle \frac{144}{169}}$