Answer: (3)12 + 6x = 84
Step-by-step explanation:
We know he definitely bought 3 books for $12 each so we immediately put that in the equation. Then we add that to the unknown (6 books times however much he bought them for) and then we equal it to 84 (his budget). Now we do 3 x 12 which is 36. Our new equation is 36 + 6x = 84. 84 - 36 = 48 so we know 6x = 48. Now divide 48 by 6 to get rid of the 6 and we learn that the variable equals 8. So, x = 8. We now know that he bought 6 books at 8 dollars each.
Answer:
3.5%
Step-by-step explanation:
Interest = 10100 - 8000 or 2100
I = Prt
2100 = 8000(9/12)r
2100 = 600r
2100/600 = r
3.5 = r
Using the normal distribution, it is found that there is a 0.2776 = 27.76% probability that the life span of the monitor will be more than 20,179 hours.
<h3>Normal Probability Distribution</h3>
The z-score of a measure X of a normally distributed variable with mean and standard deviation is given by:
- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
The mean and the standard deviation are given, respectively, by:
The probability that the life span of the monitor will be more than 20,179 hours is <u>one subtracted by the p-value of Z when X = 20179</u>, hence:
Z = 0.59.
Z = 0.59 has a p-value of 0.7224.
1 - 0.7224 = 0.2776.
0.2776 = 27.76% probability that the life span of the monitor will be more than 20,179 hours.
More can be learned about the normal distribution at brainly.com/question/24663213
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