Question

Find the 15th term of the arithmetic sequence whose common difference is d= 7 and whose first term is a1 = 5

Answer 1

Answer:

The 15th term is 103

Step-by-step explanation:

Arithmetic Sequence

An arithmetic sequence is a list of numbers with a definite pattern by which each term is found by adding or subtracting a fixed quantity to the previous term. If n is the number of the term, then:

$a_n=a_{n-1}+d$

Where d is called the common difference. If we know the first term, the nth term is calculated by:

$a_n=a_1+(n-1)*d$

The question asks us to find the term n=15 of an arithmetic sequence with a common difference d=7 and first term a1=5.

Applying the formula above:

$a_{15}=5+(15-1)*7$

$a_{15}=5+14*7$

$a_{15}=5+98=103$

The 15th term is 103