Final answer:
An arithmetic sequence with a common difference of $10 can be used to model the total amount Mr. Jones has saved to make his computer purchase. The formula to represent the sequence is aₙ = $120 + $10(n-1).
Step-by-step explanation:
An arithmetic sequence can be used to model the total amount Mr. Jones has saved to make his computer purchase. The formula for an arithmetic sequence is aₙ = a₁ + d(n-1), where aₙ represents the nth term of the sequence, a₁ is the first term, d is the common difference, and n is the number of terms.
In this case, the first term (a₁) is $120 and the common difference (d) is $10. So, the arithmetic sequence that represents the total amount Mr. Jones has saved to make his computer purchase is:
aₙ = $120 + $10(n-1)