Answer :
Answer:
a₇₃ = 450
Step-by-step explanation:
The nth term of an arithmetic sequence is
• [tex]a_{n}[/tex] = a₁ + (n - 1 )d
a₁ is the first term, d the common difference and n the term position
given
a₁₀ = 72 and a₁ = 18 . We require to find d , then
a₁ + 9d = 72 , that is
18 + 9d = 72 ( subtract 18 from both sides )
9d = 54 ( divide both sides by 9 )
d = 6
Thus
a₇₃ = 18 + (72 × 6) = 18 + 432 = 450
