Grade 9 · Math · Unit 3 of 15
Powers & Scientific Notation
Zero, negative exponents and big numbers
What your child practises
Patterns that show why a power to the zero is 1 and a negative exponent makes a reciprocal, and writing very large and very small numbers in scientific notation.
Ontario Curriculum expectation: B2.1 · the sign and size of an exponent, and scientific notation
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Write 5.7 × 10⁶ as a whole number (no spaces).
answer box
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5700000
Hint: Move the decimal point 6 places to the right, adding zeros where needed.
Question 2
Which value equals 10⁻³?
- 1/1000
- −30
- −1000
- 1/30
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1/1000
Hint: A negative exponent means the reciprocal: 10⁻³ = 1/10³ = 1/1000.
Question 3
What is 7⁰?
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1
Hint: Any non-zero number to the power 0 equals 1. Each time the exponent drops by 1 you divide by the base, and 5 ÷ 5 = 1.
Question 4
Which number is greater?
- 8 × 10⁴
- They are equal
- 6 × 10³
Show answer
8 × 10⁴
Hint: Compare the exponents first: a bigger power of ten usually wins. If they match, compare the numbers in front.
Question 5
Which value equals 10⁻²?
- −20
- 1/100
- −100
- 1/20
Show answer
1/100
Hint: A negative exponent means the reciprocal: 10⁻² = 1/10² = 1/100.
Question 6
Write 59 000 in scientific notation.
- 5.9 × 10⁴
- 5.9 × 10⁵
- 5.9 × 10³
- 59 × 10⁴
Show answer
5.9 × 10⁴
Hint: Scientific notation has one non-zero digit before the decimal point. Count how many places the decimal point moves; that is the exponent.