Rational or Irrational
Is this a rational or irrational number? Why?
2
Rational
You are finding the distance around a circular pizza with a diameter of 10 cm.
To find the distance around it (the circumference), you use:
Circumference: pi×10=10pi
Is this irrational or rational?
Is this a rational or irrational number? Why?
√21
Irrational
The teacher of a grade 6 class needs to split the students into equal groups. The class has 25 students, so ensure the groups are even she finds the square root.
Is the teacher using rational or irrational numbers? What would the size of the groups be?
Rational numbers and the square root of 25 is 5.
Is this a rational or irrational number? Why?
3.145926535897932384626433832795.....
Irrational - These are the first few digits of pi!
You walk 7 meters straight across a rectangular field instead of going 5 meters forward and 4 meters sideways along the edges.
The equation for the shortcut distance is:
√52+42=√41
Is √41 a rational or irrational number? How do you know?
√41 is an irrational number as it is a non-perfect square
Is this a rational or irrational number? Why?
2947 8/75
Rational
You are sharing a chocolate bar with a friend.
The whole bar is divided into 4 equal pieces.
You eat 1 piece, which is 1/4 of the chocolate bar.
Is your portion of the chocolate bar a rational or irrational number?
1/4 = 0.25
Does this problem use rational or irrational numbers? How do you know?
√49+0.2333333...
Rational - The square root of 49 is 7 and 0.23 is a repeating decimal.
Many Indigenous Nations use star knowledge to guide seasonal activities. Imagine a star chart where moving north is represented by a positive number and moving south is represented by a negative number. Starting at 0, if you move +7 units north to track a constellation and then -12 units south to follow another, what integer represents your final position? Is it a rational or irrational number?
-5 and Rational