Grade 9 · Math · Unit 3 of 10
Square Roots
Perfect squares and good estimates
What your child practises
Finding the square root of whole numbers, decimals and fractions that are perfect squares, and estimating the square root of other numbers by placing them between two perfect squares.
Alberta Curriculum learning outcome: N5, N6 · square roots of perfect squares, and estimating square roots that are not perfect squares
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
A square garden has an area of 64 m². How long is one side, in metres?
answer boxm
Show answer
8 m
Hint: The area of a square is side × side. Find the number that multiplies by itself to give 64: 8 × 8.
Question 2
Which is greater, √359 or 19?
- They are equal
- 19
- √359
Show answer
19
Hint: 19² = 361. 359 is less than 361, so √359 is less than 19.
Question 3
What is √0.81?
answer box
Show answer
0.9
Hint: 0.9 × 0.9 = 0.81. A decimal with 2 places has a square root with 1 place.
Question 4
Which number is a perfect square?
- 262
- 257
- 259
- 256
Show answer
256
Hint: A perfect square is a whole number times itself. 16 × 16 = 256.
Question 5
√13 is between which two whole numbers?
- 1 and 2
- 4 and 5
- 3 and 4
- 2 and 3
Show answer
3 and 4
Hint: 3² = 9 and 4² = 16. Since 13 is between 9 and 16, its square root is between 3 and 4.
Question 6
Which whole number is closest to √364?
- 19
- 20
- 18
- 21
Show answer
19
Hint: Find the perfect squares on each side of 364. 19² = 361, which is the closest to 364.