Rational or Irrational Numbers
Number Line Challenge
Root It Out
Pythagorean Power

Decimal Detectives
100

Is ¾ a rational or irrational number?

Rational 

100

Which is greater: 2 or √3?

2 is greater – √3 ≈ 1.73

100

What is the square root of 36?

6

100

What is the formula for the Pythagorean Theorem?

a² + b² = c²

100

Is 0.5 rational or irrational? Why?

Rational – it can be written as ½.

200

Is √16 a rational or irrational number?

Rational √16 = 4 

200

Plot √4 on a number line. What number is it?

2

200

What is the cube root of 64?

4

200

a² + b² = c²

If a = 3 and b = 4, what is c?

5 – √(3² + 4²) = √(9 + 16) = √25 = 5

200

Convert ⅛ into a decimal.

0.125

300

Is √2 a rational or irrational number?

Irrational – it cannot be written as a fraction and its decimal never ends or repeats

300

Which is closer to 5: √26 or √27?

√26 – √26 ≈ 5.10, √27 ≈ 5.20

300

Is 7 a perfect square? Why or why not?

No – there is no whole number that multiplies to 7.

300

Is this a right triangle: 5, 12, 13? Use the converse.

Yes – 5² + 12² = 25 + 144 = 169 = 13²

300

Is 0.333… rational? Explain.

Yes – repeating decimals are rational.

400

Is π a rational or irrational number?

Irrational – it never ends and never repeats.

400

Place √10 on a number line between two whole numbers.

Between 3 and 4 – √10 ≈ 3.16

400

What is the volume of a cube with an edge length of 3?

27 – 3 × 3 × 3

400

Find the missing side: a = 6, c = 10. What is b?

8 – b² = 10² - 6² = 100 - 36 = 64 → b = √64 = 8

400

What kind of decimal never ends and never repeats?

Irrational decimal

500

Is 0.121212... rational or irrational? Explain why.

Rational – it’s a repeating decimal, and can be written as a fraction.

500

Which number is between √8 and √9 on the number line?

Any number between 2.83 and 3 – example: 2.9

500

If a cube has a volume of 125, what is the edge length?

5 – ∛125 = 5

500

A triangle has sides 7, 24, and 25. Is it a right triangle?

Yes – 7² + 24² = 49 + 576 = 625 = 25²

500

Explain why 0.727272... is a rational number.

It repeats and can be written as a fraction (8/11).