Question

In an arithmetic sequence an, if a1 = 5 and d = 3, find a72. A) 216 B) 218 C) 221 D) 223

Answer 1

b

Explanation:

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Answer 2

B. 218

Explanation:

Step 1

The first step is to write down the formula for an arithmetic sequence and state the given values. The formula for an arithmetic sequence is

`a_n=a_1+(n-1)d.` We are given that
`a_1=5,d=3`

Step 2

Determine the term that is required. We are required to find the 72nd term of the sequence. We will use the formula to calculate this term as shown below,

`a_n=a-1+(n-10d\\ a_(72)=5+(72-1)* 3\\a_(72)=5+71* 3\\a_(72)=218`