For questions 3 - 4, identify the symbol that correctly relates the two numbers, and then determine
which number would be to the left of the other on a number line.
3. 17? 25 4. 42 ? 39



Sagot :

9514 1404 393

Answer:

  3. 17 < 25 . . . . 17 is on the left

  4. 42 > 39 . . . . 39 is on the left

Step-by-step explanation:

3. If you do any counting at all, you know that starting from 1, you reach the number 17 before you reach the number 25. That is 17 is less than 25.

The numbers increase to the right on the number line, so the relationship is ...

  17 < 25 . . . . . . . . 17 is to the left

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4. You can count to 39 sooner than you can count to 42.

  42 > 39 . . . . . . . . 39 is to the left

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Additional comment

The point of the symbol (< or >) indicates the smaller value. The wider open end of the symbol indicates the larger value. One could say the symbol points to the number that is left on the number line.

Given a choice as to how to write an inequality, I often find it beneficial to write it so the "arrow" points to the left. That way, the written order of the operands corresponds to their relative locations on the number line.

For example, x < 3 means the number line will be shaded to the left of 3 to indicate possible values of x. 3 > x means the same thing, but requires more mental effort to figure out how to draw it on the number line.

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"Back in the day" we played games that required counting. Jump rope or hide-and-seek, for example. It became obvious that it took 10 times as long to count to 100 as to count to 10. That is, the place values of the digits in a number were quite clear, as was their order.