<h3>
Answer: 2.325</h3>
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Work Shown:
The shortcut way to do this is to plug a = 1.2, r = 0.5 and n = 5 into the formula below.

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The longer way is to generate the first five terms, then add them up. To generate the terms, we multiply each term by 0.5 to get the next one.
a1 = first term = 1.2
a2 = second term = 0.6, result of multiplying 0.5 and 1.2
a3 = third term = 0.3
a4 = fourth term = 0.15
a5 = fifth term = 0.075
Now add up the five terms
a1+a2+a3+a4+a5 = 1.2+0.6+0.3+0.15+0.075 = 2.325
This method isn't too tedious since n = 5 isn't too large. For large values of n, it is better to use the formula shown in the previous section.
Answer:

where y is in thousands
Step-by-step explanation:
The equation in two variables that can be used to represent the situation given can be determined using computer software such Stat-Crunch or Ms. Excel or advanced calculators.
I shall use Ms. Excel for this question.
In Ms. Excel, enter the data into any two adjacent columns. Next, highlight the data, then click the insert ribbon and select the scatter-plot option.
Excel returns a scatter-plot chart as shown in the attachment below.
After obtaining the scatter-plot, we shall need to add a trend line in order to determine the mathematical equation that best fits the scenario given.
Click anywhere inside the chart, then select the design tab under chart tools. Click on the Add Chart element in the upper left corner of the excel workbook and select more trend-line options. This feature will enable us to fit any trend-line to our data.
Select the exponential option, since we were informed that he number of flip cell phones is in exponential decline,ensuring you check the box; Display Equation on chart.
Find the attached.
The equation in two variables is thus;

Answer:
-0.9
Step-by-step explanation:
-1.7 - (-0.8)
= -1.7 + 0.8
= -0.9
Three to the power of negative four is 81
Answer:
The simplified expression is:

Step-by-step explanation:
Given the expression





Add similar elements




Thus, the simplified expression is:
