Question

A store had 100 t-shirts. Each month, 30% of the t-shirts were sold and 25 new t-shirts arrived in shipments. Which recursive function best represents the number of t-shirts in the store, given that f(0) = 100? A. f(n) = f(n - 1) • 0.3 + 25, n > 0 B. f(n) = 100 - f(n - 1) • 0.3 + 25, n > 0 C. f(n) = f(n - 1) • 0.7 + 25, n > 0 D. f(n) = 100 - f(n - 1) • 0.7 + 25, n > 0

Answer 1

f(n)=f(n-1)*0.7+25 is the answer

Answer 2

If 30% of the t-shirts are sold, then f(n) includes f(n-1)*0.7.  If we add 25 new t-shirts, the total value of f(n) is f(n-1)*0.7+25.  C is the correct answer.