Function Notation Word Problems

Terence’s spending account balance is represented by the formula, A(t)=1000(0.9)^t, where t is time elapsed in weeks. What will his account balance be after 2 weeks?

• 41
• 45
• 81
• 90

The function h(t) = 300 – 16t represents the height of a ball (in feet) dropped from 300 feet after t seconds. What will be the height of the ball after 2.4 seconds?

• 38.4
• 261.6
• 338.4
• 384

Mr. Levy invested $6,500 at a 4.5% annual interest rate. The function f(t) = 6,500(1.045)^t models the value of the investment after t years. What is the value of the investment after 18 months?

• $6,872.56
• $6,943.65
• $11,349.20
• $14,355.11

What is the value of f(–6) for the function  f(x)=.5x-7?

• -10
• -4
• 4
• 10

An Internet company uses the function f(x) = 6.052(1.378)^x to predict the number of subscribers (in millions) x years after 2000. Approximately what is the predicted number of Internet subscribers the company will have in 2019?

• 442 million
• 1 billion 943 million
• 2 billion 677 million
• 3 billion 689 million