Writing Exponential - word problems

Evan's parents give him an allowance as follows: $1 in January, $2 in February, $4 in March and so on, doubling the amount he receives each month. Create the table on your paper. What is the common ratio?

• Multiply by 1

• Multiply by 2

• Multiply by 0.5

• Divide by 2

Evan's parents give him an allowance as follows: $1 in January, $2 in February, $4 in March and so on, doubling the amount he receives each month. How much allowance will he receive in August?

• $64
• $128
• $256
• $14

Which sequence has a common ratio of 1.5?

A. 2, 3, 4.5, 6.75

B. 2, 3.5, 5, 6.5

C. 2, 4/3, 8/9, 16/27

D. 2, 3.5, 5.25, 7.875

• A

• B

• C

• D

Does the table represent a linear or exponential function? Write the function. 
*show your work on your paper*

• linear:
  y = -60x + 240
• linear:
  y = .75x + 240
• exponential:
  y = 240(.75)^x
• exponential: 
  y = .75(240)^x

Does the table represent a linear or exponential function? Write the function. 
*show your work on your paper*

• linear: 
  y = 12x + 12
• linear:
  y = 2x + 12
• exponential: 
  y = 12(2)^x
• exponential: 
  y = 2(12)^x

In its first 4 years of operation, a certain company increased its revenue by 2.5% each month. Write the function relating the variables.

*Show work on your paper*

• y = 800(1.025)^x

• y = 1.025(800)^x

• y = 20x + 800

• y = 800(1.025)^x

In its first 4 years of operation, a certain company increased its revenue by 2.5% each month. If this pattern continues, what would be the company’s monthly revenue at the end of 1 year?
*Show work on your paper*

• $1049.70
• $1102.80
• $9840
• $1075.91

Evan made a fresh pot of coffee then measured its temperature in 3-minute intervals over a period of 15 minutes, as shown in the table. Does the data show exponential growth or exponential decay? 

• Exponential growth because as time increases, the temperature decreases. 
• Exponential growth because as time increases, the temperature decreases. 
• Exponential decay because as time increases, the temperature decreases. 
• Exponential decay because as time increases, the temperature increases. 

Evan made a fresh pot of coffee then measured its temperature in 3-minute intervals over a period of 15 minutes, as shown in the table. Write an exponential model for this data.

*Show work on your paper*

• f(x) = 0(1.04)^x

• f(x) = 180.2(1.04)^x

• f(x) = 0.95(180.2)^x

• f(x) = 180.2(0.95)^x

Evan made a fresh pot of coffee then measured its temperature in 3-minute intervals over a period of 15 minutes, as shown in the table. Use your exponential model to determine the appropriate temperature after 30 minutes.
*Show work on your paper*

• 38.68 degrees
• 107.89 degrees
• 70.4 degrees
• 113.57 degrees