Answer:
Step-by-step explanation:
given that certain tubes manufactured by a company have a mean lifetime of 800 hours and a standard deviation of 60 hours.
Sample size n =16
Std error of sample mean = 
x bar follows N(800, 15)
the probability that a random sample of 16 tubes taken from the group will have a mean lifetime
(a) between 790 and 810 hours,
=
(b) less than 785 hours
, (c) more than 820 hours,
(d) between 770 and 830 hours
=
Answer:
Given
The area of a rectangle is less than 81 square centimeters
length 9cm
width =x cm
Step-by-step explanation:
Area of rectangle=length ×width
= 9×X
Area of rectangle is less than 81 cm^2
So 9x-81=0
X=81/9
X=9
So the value of xis 9
Answer: 6 cases
pls give brainliest if this helped
Step-by-step explanation:
You're expression is correct if it's asking for a number that is less than 7. But if the problem is asking for some number less than seven as in seven less some number, then it's 7-n. For example: 4 less than 7 is 7-4.
Hope this helps!
