Writing Exponential Functions from Word Problems

This video tutorial covers evaluating exponential expressions in word problems through three examples. The first example involves bacteria growth in a petri dish, demonstrating how to write and evaluate an exponential function. The second example discusses the growth of nano-related patents in the US, while the third example illustrates the depreciation of a computer's value over time. Each example includes identifying initial values, growth or decay factors, and variables, followed by writing and evaluating the corresponding exponential expressions.

What is the main focus of this video?

• Evaluating linear expressions in word problems

• Evaluating exponential expressions in word problems

• Solving quadratic equations

• Understanding logarithmic functions

In the first example, what is the initial number of bacteria in the petri dish?

• 1.2

• 1000

• 500

• 600

What is the growth factor for the bacteria in the petri dish example?

• 2.0

• 1.2

• 0.8

• 0.5

How many bacteria will there be after 3 hours in the petri dish example?

• 500

• 864

• 720

• 600

In the second example, what year is used as the initial value for the number of nano-related patents?

• 1990

• 1985

• 1991

• 2000

What is the growth factor for the number of nano-related patents?

• 1.5

• 0.8

• 1.2

• 2.0

How many nano-related patents are there in 1998?

• 215

• 200

• 100

• 150

In the third example, what is the initial value of the computer?

• 1000 dollars

• 800 dollars

• 900 dollars

• 700 dollars

What is the decay factor for the computer's value?

• 0.5

• 0.3

• 1.3

• 0.7

What is the value of the computer after 5 years?

• 200 dollars

• 150.26 dollars

• 300 dollars

• 100 dollars