Exponent Word Problem

A bacteria culture starts with 1000 bacteria and doubles every hour. Write an exponential expression to represent the number of bacteria after x hours.

• 1000 / 2^x

• 1000 * x^2

• 1000 * 2^x

• 1000 + 2^x

Tags

CCSS.HSF.LE.A.2

If a car depreciates by 20% each year, write an exponential expression to represent the value of the car after x years if it was originally worth $10,000.

• $10,000 * (0.8)^x

• $10,000 * (0.2)^x

• $10,000 * (1.2)^x

• $10,000 * (0.5)^x

Tags

CCSS.HSF.LE.A.2

A radioactive substance decays by 30% every 5 hours. Write an exponential expression to represent the amount of substance remaining after x hours if the initial amount was 500 grams.

• 500 * (0.7)^(x/5)

• 500 * (0.3)^(x/5)

• 500 * (0.7)^(x)

• 500 * (0.3)^(5/x)

A population of rabbits triples every month. Write an exponential expression to represent the population after x months if there were originally 50 rabbits.

• 50 * x^3

• 50 * 3x

• 50 * 3^x

• 50 + 3^x

Tags

CCSS.HSF.LE.A.2

Eduardo currently has 500 followers on TikTok. He makes a video after the basketball game and it goes viral! Since he became internet famous, the number of followers is increasing by 25% daily. Write an exponential function that represents the relationship between x, the number of days since Eduardo posted the video and y, the total number of followers Eduardo has.

Mathematical Equivalence

ON

Tags

AI.9.9.C

A new savings account is opened with $400 and gains 3% every year. What is the exponential function?

y = ​ (a)   ( 1 ​ (b)   ​ (c)   )^x (^ means to power of x - x is the exponent)

• 400

• +

• 0.03

• 3

• 0.3

• 0.97

• 4

Tags

CCSS.HSF.LE.A.2

If an investment grows by 5% each quarter, write an exponential expression to represent the value of the investment after x quarters if the initial amount was $500.

• $500 * (1.5)^x

• $500 * (1.05)^{x+1}

• $500 * (1.05)^(2x)

• $500 * (1.05)^x

Tags

CCSS.HSF.LE.A.2

A forest fire spreads to double its size every 6 hours. Write an exponential expression to represent the size of the fire after x hours if it originally covered 10 acres.

• 10 * 2^(x/6)

• 10 * 2^(6/x)

• 10 * 2^(x-6)

• 10 * 2^(x*6)

Tags

CCSS.HSF.LE.A.2

If a city's population increases by 10% each year, write an exponential expression to represent the population after x years if it originally had 100,000 residents.

• 100,000 * (1.10)^x

• 100,000 + (1.10)^x

• 100,000 * (1.10)^-x

• 100,000 * (1.10)^2x

Tags

CCSS.HSF.LE.A.2

A bank account earns 3% interest compounded annually. Write an exponential expression to represent the balance after x years if the initial deposit was $2000.

• $2000 * (1 + 0.03)^2x

• $2000 * (1 + 0.03)^{x+1}

• $2000 * (1 + 0.03)^{x-1}

• $2000 * (1 + 0.03)^x