Estimating Quantities with Powers of 10

This lesson focuses on using powers of 10 to estimate and compare large and small quantities. It covers examples such as comparing populations of Japan and China, speeds of light and sound, thickness of hair and paper, and GDP of Canada and the US. The lesson concludes with a problem on comparing the number of cars worldwide to those in the US, emphasizing the use of powers of 10 for estimation.

What is the main focus of lesson 28?

• Solving algebraic equations

• Understanding fractions

• Learning basic arithmetic

• Using powers of 10 to estimate quantities

How do you estimate the population of Japan using powers of 10?

• By subtracting 10 from the population

• By rounding to the nearest power of 10

• By rounding to the nearest hundred

• By adding 10 to the population

What is the estimated population of China when rounded to the nearest power of 10?

• 1 * 10^9

• 1 * 10^7

• 1 * 10^6

• 1 * 10^8

How do you compare the speed of light and sound using powers of 10?

• By adding their speeds

• By subtracting their speeds

• By dividing their speeds

• By multiplying their speeds

Which travels faster, light or sound?

• It depends on the medium

• Both travel at the same speed

• Light

• Sound

How do you estimate the thickness of a human hair using powers of 10?

• By subtracting 10 from the thickness

• By adding 10 to the thickness

• By rounding to the nearest power of 10

• By rounding to the nearest whole number

What is the estimated thickness of a sheet of paper when rounded to the nearest power of 10?

• 1 * 10^-3

• 1 * 10^-1

• 1 * 10^-4

• 1 * 10^-2

How many times greater is the GDP of the United States compared to Canada?

• 5 times

• 10 times

• 20 times

• 15 times

What is the estimated number of cars in the world using powers of 10?

• 1 * 10^7

• 1 * 10^9

• 1 * 10^6

• 1 * 10^8

How do you compare the number of cars in the world to that in the USA using powers of 10?

• By multiplying the numbers

• By dividing the numbers

• By subtracting the numbers

• By adding the numbers