5. Challenge: Subtracting Base-10 Numbers

In this challenge, you will subtract numbers with multiple digits.

Sequencing

Subtracting numbers with multiple digits is a variation of adding numbers with multiple digits, which was presented in a previous module. Learners can use their knowledge of addition to complete the Problems in this module, without explicitly being shown how to do subtraction.

Problem 1

  69
- 28
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Sequencing

Subtract two digits (with no borrows and no missing digits). This is a variation of the process for addition.

Problem 2

  427
- 259
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Sequencing

Subtract three digits (with consecutive borrows and no missing digits). This is a variation of the process for addition.

Problem 3

 103
-  9
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Sequencing

Subtract three digits (with consecutive borrows and missing digits).

This is a variation of the process for addition.

Problem 4

During the subtraction process, what indicates that the result will be negative (less than zero)?

Sequencing

Attempting to borrow from a 0 leading digit.

This is a variation of the process for addition.