Question

5. What is the 38th term of the arithmetic sequence where *

(5 Points)
a4 = 8.5 and az = 13
O 59.5
O 61
O 64
65.5

Answer 1

A 59.5 is the answer

Answer 2

• A. 59.5

Explanation:

Given AP with

• a₄ = 8.5 and a₇ = 13
• a₃₈ = ?

Equation for nth term:

• aₙ = a₁ + (n - 1)d

Use same for given terms:

• a₄ = a₁ + 3d = 8.5
• a₇ = a₁ + 6d = 13

Subtract the last two equations:

• 3d = 13 - 8.5
• d = 4.5/3
• d = 1.5

Find a₁:

• a₁ = 8.5 - 3*1.5 = 4

Now find a₃₈:

• a₃₈ = 4 + 1.5*37 = 59.5

Correct choice is A