The Other Side of Zero | IT

Question 10

Should we write 3<4-3 < -4 or 4<3-4 < -3?

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Solution
Understand the Question
  • On a number line, numbers increase as you move to the right and decrease as you move to the left.
  • To compare 3-3 and 4-4, look at their relative positions on the number line: the number further to the right is greater, and the number further to the left is smaller.
  • The symbol << means "less than" (smaller than), and >> means "greater than" (bigger than).

Step 1 · Compare Positions on the Number Line

On a number line, numbers get larger as we move to the right and smaller as we move to the left.Diagram 1

Since 3-3 lies to the right of 4-4, 3-3 is greater than 4-4, which means 4-4 is smaller than 3-3.

Step 2 · Write the Comparison

Since 4-4 is smaller than 3-3, we use the symbol '<<' (less than): 4<3-4 < -3

This can also be written using the symbol '>>' (greater than) as: 3>4-3 > -4

Answer

We should write 4<3-4 < -3.

Common Mistakes
  • Comparing Magnitudes Directly: Incorrectly assuming 4>3-4 > -3 because 4>34 > 3. For negative numbers, the number with the larger absolute value is further to the left and hence smaller.
  • Inequality Symbol Confusion: Confusing << (less than) and >> (greater than). Remember that the open/wider end always faces the larger number.

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