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Student Question

Grade 6 • 5mo.

I’m not sure of what I’m supposed to be doing when I did this calculation and I need a quick review to help me understand. Thank you 😊



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Explanations (1)

  • Explanation from Alloprof

    Explanation from Alloprof

    This Explanation was submitted by a member of the Alloprof team.

    Team Alloprof • 5mo. edited September 2022


    Thank you for your question! :D

    To do this subtraction, you'll need to borrow a 1 from the number at the position before, and you'll need to do that each time you are not able to do the subtraction directly.

    Because we are not able to calculate 0 - 9, we need to borrow a 1 from the hundreds. However, we also have a zero at the hundreds. The only number we are able to borrow from is the 4. Therefore, the 4 will become a 3, and the position just after a 10.


    Then, we'll borrow again, this time from the 10, who will become a 9.


    And so on... until we reach the position of the units :


    Then, we will finally be able to subtract 9 from 10, and you'll be able to do the rest of the subtraction as per usual.

    Here's a video that might help you understand this notion better : Maths Class 3 Substraction - YouTube

    You can also follow this link to find more similar examples :

    La soustraction de nombres entiers naturels | Secondaire | Alloprof

    You can translate the page into English by copying and pasting it in Google Traduction.

    Let us know if we can help you with anything else! :)