Math111i_GroupQuiz5_Solutions

# Math111i_GroupQuiz5_Solutions - 0) and their business grows...

This preview shows pages 1–2. Sign up to view the full content.

Math 111I Sec 001 Group Quiz 5 Solutions Name Directions: Read each question carefully and answer in the space pro- vided. The use of calculators is allowed, but not necessary. There are 10 points possible. To receive partial credit on any problem work must be shown. 1. Write a function in the form f ( x ) = C · a x for an exponential function with an initial value of 3,700 whose output triples for each unit increase of the input. Solutions. The initial value is C = 3700, and from the description we see that a = 3. So the function follows as f ( x ) = 3700 · 3 x . 2. Determine if the data is linear or exponential. Write the equation of the function x -1 0 1 2 f ( x ) 3.01 5.50 10.07 18.42 Solutions. We check to see if f ( x ) is exponential 5 . 50 3 . 01 1 . 83 10 . 07 5 . 50 1 . 83 18 . 42 10 . 07 1 . 83 So, we notice that f (0) = C and we have that C = 5 . 50 so we have that f ( x ) = 5 . 50(1 . 83) x . 3. A new cell phone company has 400 subscribes their ﬁrst year (year

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 0) and their business grows to 600 subscribers the next year (year 1). Write a formula for the number of subscribers, N ( t ), as a function of years in business t , assuming exponential growth. Math 111I Sec 001 Group Quiz 5 Solutions Solutions. Clearly we have that if N ( t ) = Ca t , and we know that N (0) = 400 = C , and we also see that a = 600 400 = 1 . 5 Thus we have that N ( t ) = 400(1 . 5) t . 4. Find the growth/decay factor (assuming exponential growth/decay) for a population that decreases from 11,000,000 to 9,790,000 in one year. Solutions. We have that we decreased over one time period. So the decay factor for each year is a = 11 , 000 , 000 9 , 790 , 000 = 0 . 89...
View Full Document

## Math111i_GroupQuiz5_Solutions - 0) and their business grows...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online