Answer:
(A) 21
Step-by-step explanation:
5x-15 needs to equal 90 since it is a right angle and 21 makes that true

Answer:
The third option, -1/2(30) = -15
Step-by-step explanation:
If it decreases by 1/2, we know it has to be -1/2, and the days we are given are 30. We need to multiply -1/2 by 30 in order to find the water level after 30 days, which would be -15 (inches?) I hope this helped.
All together there are 15 pieces of fruit
out of 15, 6 of them are lemons.
the probability that the fruit will be a lemon is
6/15
which reduces to
2/5
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
8.66
that is the answer for me