5.) Find the 18th term of the sequence where a,= 3 and d = 7?
a. 129
b. 136
c. 119
d. 122
Answers
Answer:
122
Step-by-step explanation:
In mathematics, arithmetic progression also known as an arithmetic sequence is define as a sequence of numbers such that the two consecutive terms has a common difference. Common difference means the second minus the first one.
Arithmetic Sequence Formula
Finding nth term: an= a1 + (n-1)d
Finding sum: sn= 1/2n(a1+an)
Where
an is the nth term
sn is the sum of all terms
a1 is the first term
n is the number of terms
d is the common difference
In the given problem: Given
a1= 3, d= 7 n= 18
Since, you are being ask to solve for 18th term. Just use the first formula for finding nth term.
Solution
an= a1+(n-1)d
18th= 3+(18-1)7
18th= 3 + (17)7
18th= 3 + 119
18th= 122
Therefore, the 18th term is 122.
hope it's help full
it's wrong means I am sorry
Answer:
d. 122
Step-by-step explanation:
an=a+(n-1)d
a18=3+18-1×7
=3+17×7
=3+119
=122