Answer:
so what are the equations you're having trouble with?
Answer:
0.8041 = 80.41% probability that a given battery will last between 2.3 and 3.6 years
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
A certain type of storage battery lasts, on average, 3.0 years with a standard deviation of 0.5 year
This means that 
What is the probability that a given battery will last between 2.3 and 3.6 years?
This is the p-value of Z when X = 3.6 subtracted by the p-value of Z when X = 2.3. So
X = 3.6



has a p-value of 0.8849
X = 2.3



has a p-value of 0.0808
0.8849 - 0.0808 = 0.8041
0.8041 = 80.41% probability that a given battery will last between 2.3 and 3.6 years
% means out of a hundred. So, 140% should be 140/100.
Answer:


Step-by-step explanation:
Open the brackets first:

Simplify:

It is determined that this can't be factored, so rewrite the equation so you can complete the square.

Take the square of 1.5 and add it to both sides:

Factor:


or 
So 
or 
Answer:
34. a) 10 students
35. b) Together green and red make up the half of the students
Step-by-step explanation:
For number 34, the answer is 10 because it is one-fourth of 40 which is same as 40 divided by 4 which is 10.
For 35, green and red do not add up to one half
Hope it helped you!