Answer:
5
Step-by-step explanation:
[math]
U_{n} = 5n - 2 \\
Common Difference = U_{n+1} - U_{n} \\
= [5(n + 1) - 2] - [5n - 2] = [5n + 5 - 2] - [5n - 2]\\
= 5n + 5 - 2 - 5n + 2\\
= 5
[/math]
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Question
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Split the fraction on the left
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Take away h/5 from both sides
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Change the denominator to be the same
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Put it into single fraction
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Rearrange (This step may not be necessary)
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-43 - 4r = 3 - 27r
Add 27r to both sides. -43 - 4r + 27r = 3 -27r + 27r or -43 + 23r = 3
Add 43 to both sides. -43 + 43 +23r = 3 + 43 or 23r = 46.
Divide both sides by 23 to get r by itself. 23r / 23 = 46 / 23 or r = 2
r = 2
Answer should be 1.85 x 10^18
60 total fourth graders and 43 are girls. To find the number of boys, subtract.
60 - 43 = 17 boys
If 5 girls were absent, subtract.
43 - 5 = 38 girls present
If 4 boys were absent, subtract.
17 - 4 = 13 boys present
Therefore, there were 13 boys present.
Best of Luck!