This video tutorial for grade 8 math covers the addition and subtraction of numbers using scientific notation. It begins with an introduction to scientific notation, explaining its purpose in simplifying the representation of very large or small numbers. The video outlines the rules for writing numbers in scientific notation, emphasizing the importance of having one digit before the decimal point. It then demonstrates how to add and subtract numbers in scientific notation by aligning the powers of ten, either directly or by converting to standard form. The tutorial concludes with a brief mention of upcoming topics on multiplication and division in scientific notation.

What is the primary purpose of using scientific notation?

• To make numbers look more complex

• To avoid using decimals

• To simplify the writing of very large or small numbers

• To convert numbers into fractions

Which of the following is a correct representation of 93,000 in scientific notation?

• 9.3 x 10^4

• 93 x 10^4

• 9.3 x 10^3

• 0.93 x 10^5

What must be true about the multiplier in scientific notation?

• It must be less than 1

• It must be greater than or equal to 10

• It must be between 1 and 10

• It can be any number

When adding numbers in scientific notation, what must be done first?

• Convert to fractions

• Add the exponents

• Subtract the smaller number

• Align the powers of ten

How do you convert 2 x 10^4 to standard form?

• 20000

• 2000

• 200000

• 200

What is the result of adding 2 x 10^4 and 1.5 x 10^3 in scientific notation?

• 2.15 x 10^3

• 3.5 x 10^4

• 21.5 x 10^3

• 2.15 x 10^4

In the example of adding 1.25 x 10^5 and 3.5 x 10^3, what is the first step?

• Subtract the exponents

• Align the powers of ten

• Convert to standard form

• Multiply the numbers

What is the result of adding 1.25 x 10^5 and 3.5 x 10^3 in scientific notation?

• 1.6 x 10^3

• 1.285 x 10^3

• 1.6 x 10^5

• 1.285 x 10^5

When subtracting in scientific notation, what must be done first?

• Align the powers of ten

• Add the exponents

• Convert to fractions

• Multiply the numbers

What is the result of subtracting 2 x 10^3 from 7.4 x 10^4 in scientific notation?

• 5.4 x 10^4

• 7.2 x 10^4

• 5.4 x 10^3

• 7.2 x 10^3