Answer:
400
Step-by-step explanation:
First, the firm produces 100 sets its first year. This means that our equation starts at 100. Next, the total number of calculator sets in 5 years is 4500. With y₁ representing the amount of calculator sets produced during year 1, y₂ representing the amount of sets during year 2, and so on, we can say that
y₁+y₂+y₃+y₄+y₅ = 4500
100 + y₂+y₃+y₄+y₅ = 4500
Next, we are given that the production increases uniformly by an amount each year. Representing that amount as a, we can say that
y₁+a = y₂
y₂+a = y₃
y₁+a+a = y₃
y₁+ 2 * a = y₃
and so on, so we have
100 + y₂+y₃+y₄+y₅ = 4500
100 + (100+a) + (100+2a) + (100+3a) + (100+4a) = 4500
500 + 10a = 4500
subtract 500 from both sides to isolate the a and its coefficient
4000 = 10a
divide both sides by 15 to isolate a
a = 400