Use the explicit formula [tex]a_n = a_1 + (n - 1) \cdot d[/tex] to find the 500th term of the sequence below.

[tex]24, 30, 36, 42, 48, \ldots[/tex]

A. 2994
B. 3018
C. 3024
D. 3042



Answer :

To find the 500th term of the arithmetic sequence given by [tex]\( 24, 30, 36, 42, 48, \ldots \)[/tex], we will use the explicit formula for the [tex]\( n \)[/tex]-th term of an arithmetic sequence:

[tex]\[ a_n = a_1 + (n - 1) \cdot d \][/tex]

where:
- [tex]\( a_n \)[/tex] is the [tex]\( n \)[/tex]-th term,
- [tex]\( a_1 \)[/tex] is the first term,
- [tex]\( d \)[/tex] is the common difference,
- [tex]\( n \)[/tex] is the number of the term.

Given:
- First term ([tex]\( a_1 \)[/tex]) is 24,
- Common difference ([tex]\( d \)[/tex]) is the difference between any two consecutive terms. Here, [tex]\( d = 30 - 24 = 6 \)[/tex],
- [tex]\( n = 500 \)[/tex] (we need to find the 500th term).

Substituting these values into the formula, we have:

[tex]\[ a_{500} = 24 + (500 - 1) \cdot 6 \][/tex]

Now, calculate step-by-step:

[tex]\[ a_{500} = 24 + (499) \cdot 6 \][/tex]

[tex]\[ a_{500} = 24 + 2994 \][/tex]

[tex]\[ a_{500} = 3018 \][/tex]

Therefore, the 500th term of the sequence is [tex]\( 3018 \)[/tex].

Comparing this result with the given answer choices:
A. 2994
B. 3018
C. 3024
D. 3042

The correct answer is B. [tex]\( 3018 \)[/tex].