Answer: 

<u>Step-by-step explanation:</u>
a) This is an arithmetic sequence where 3 is added to the previous term.
48 + 3 = 51
51 + 3 = 54
54 + 3 = 57
The recursive formula for this sequence is:
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b) This is a geometric sequence where 2.5 is multiplied to the previous term.
100(2.5) = 250
250 (2.5) = 625
625(2.5) = 1562.5
The recursive formula for this sequence is: 
Answer:
x=5 1/4
Step-by-step explanation:
2 1/4=
--->
divided by 3 to find 1/7x---->
=1/7x---> x=21/4---> x=5 1/4
Answer:
X<12 first choice.
Step-by-step explanation:
5(x+5) <85
5x +25 < 85
5x <60
X<12
Hope this helps..
The Arithmetic Mean and Median of the given set of data ( 2, 5, 13, 15, 19, 21 ) are 12.5 and 14 respectively.
<h3>What is Arithmetic mean?</h3>
Arithmetic mean is simply the average of a given set numbers. It is determined by dividing the sum of a given set number by their number of appearance.
Mean = Sum total of the number ÷ n
Where n is number of numbers
Median is the middle number in the data set.
Given the sets;
Mean = Sum total of the number ÷ n
Mean = (2 + 5 + 13 + 15 + 19 + 21) ÷ 6
Mean = 75 ÷ 6
Mean = 12.5
Median is the middle number in the data set.
Median = ( 13 + 15 ) ÷ 2
Median = 14
Therefore, the Arithmetic Mean and Median of the given set of data ( 2, 5, 13, 15, 19, 21 ) are 12.5 and 14 respectively.
Learn more about arithmetic mean here: brainly.com/question/13000783
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