Answer:
x = 1
Step-by-step explanation:
Step 1: Write equation
9 - 2x = 7x
Step 2: Solve for <em>x</em>
<u>Add 2x on both sides:</u> 9 = 9x
<u>Divide both sides by 9:</u> x = 1
Step 3: Check
<em>Plug in x to verify it's a solution.</em>
9 - 2(1) = 7(1)
9 - 2 = 7
7 = 7
Answer:
The bulbs should be replaced each 1436.9 hours.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

How often should the bulbs be replaced so that no more than 1% burn out between replacement periods?
This is the first percentile of hours. So it is X when Z has a pvalue of 0.01.
So it is X when Z = -2.33.




The bulbs should be replaced each 1436.9 hours.
Answer:
Hope this helps :) look at the picture because I dont know how to type that
Step-by-step explanation:
Yes she can find the average colour by adding up all the amount of colors by how many colors there are.
Answer:
Step-by-step explanation: just search it up