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Example Questions
Example Question #2 : Arithmetic Sequences
What is the th term in the following series of numbers: ?
148
Notice that between each of these numbers, there is a difference of . This means that for each element, you will add . The first element is or . The second is or , and so forth... Therefore, for the th element, the value will be or .
Example Question #21 : Sequences
Find the sum of the first fifteen terms in an arithmetic sequence whose sixth term is and whose ninth term is .
Use the formula an = a1 + (n – 1)d
a6 = a1 + 5d
a9 = a1 + 8d
Subtracting these equations yields
a6 – a9 = –3d
–7 – 8 = –3d
d = 5
a1 = 33
Then use the formula for the series; = –30
Example Question #1 : How To Find The Next Term In An Arithmetic Sequence
Given the sequence of numbers:
1, 5, 9, _ , _ , 21 ....
What are the two missing terms of the arithmetic sequence?
12, 18
14, 17
13, 16
14, 16
13, 17
13, 17
The sequence is defined by an = 4n – 3 for such n = 1,2,3,4....
Example Question #1 : How To Find The Next Term In An Arithmetic Sequence
What is the next term in the following sequence?
What is the next term in the following sequence?
This is an arithmetic sequence with a common difference of . To find the next term in an arithmetic sequence, add the common difference to the previously listed term:
Example Question #1 : How To Find The Next Term In An Arithmetic Sequence
Find the sixth term in the following number sequence.
This question can be answered by analyzing the sequence provided and determining the pattern. The first term is , and the second term is The third term is Thus, has been added to in order to obtain , and has been added to in order to obtain This shows that is added to each preceding term in the sequence in order to obtain the next term. The complete sequence from terms one through six is shown below.
Thus, the sixth term is
Example Question #3 : How To Find The Next Term In An Arithmetic Sequence
What is the next term of the series ?
Begin by looking at the transitions from number to number in this series:
From to : Add
From to : Subtract
From to : Add
From to : Subtract
From what you can tell, you can guess that the next step will be to add . Thus, the next value will be .
Example Question #2 : How To Find The Next Term In An Arithmetic Sequence
What is the next term in the following sequence: ?
This sequence is a little tricky. Notice that the second element is equal to the first. After that, the third is equal to the sum of the first two , next the fourth is equal to the sum of the second and the third , and the same continues for each element after this. Thus, the next element in the series will be equal to or .
Example Question #1 : How To Find The Next Term In An Arithmetic Sequence
What is the next term in the sequence?
The difference between each term is constant, thus the sequence is an arithmetic sequence.
Simply find the difference between each term, and add it to the last term to find the next term.
Example Question #1 : How To Find The Missing Number In A Set
Ryan’s class lined up in order of birthdays. If Ryan is the 11th oldest and 9th youngest, how many students are in his class?
21
18
20
11
19
19
Ryan is the 11th oldest and 9th youngest, so there are 10 students older than him and 8 younger than him. The 10 older plus the 8 younger plus Ryan himself gives a total of 10+8+1 = 19. (The trick is not to double-count Ryan.)
Example Question #1 : How To Find The Missing Number In A Set
What is the next integer in this series of numbers?
1, 4, 7, 10, 13, ?
16
17
15
14
18
16
Each number is the previous number + 3.
Example: 1 + 3 = 4
13+3 = 16
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