 ## Question

primary 5 | Maths | Whole Numbers

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##### Sushi

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Hi Tutor, sincerely need your help for this question. Thank you in advanced !

Date Posted: 6 months ago
Views: 241
Eric Nicholas K
6 months ago
57 x 28 = box x 7 x 4 - 56 - 3 x 28

Notice that for multiplication, 7 and 4 can be done together (since box, 7 and 4 are multiplied together)

Also notice that 56 = 2 x 28
57 x 28 = box x 28 - 2 x 28 - 3 x 28

Let me replace “28” by “apples”
57 apples = box apples - 2 apples - 3 apples

Does it look better now?
57 = box - 2 - 3

What is the value of box?

62.
Sushi
6 months ago
Thank you Tutor for the good method!!!

58 x 28 = 1596
3 x 28 = 84
84 +1596 = 1680
1680 +56 = 1736
1736 / 4 = 434
434 / 7 = 62
clear {{ downvoteCount * -1 }} Downvotes
Date Posted: 6 months ago
Sushi
6 months ago
Hi Tutor, i dun really understand the solution given. Hope you could explain again, thank you!
Sushi
6 months ago
Thank you Tutor!
Using BODMAS, the order of mathematical operation is as follows:
In this question, we only focus on Division-> Multiplication-> Addition‐>Subtraction

Hence, subtraction/addition one side does not affect the multiplication/division on the same side and we can solve the question like so:
57×28=⬜×7×4-56-3x28
1596=⬜×7×4-56-84
1596=⬜×7×4-140
To bring the -140 over to the left side,
1596+56+84=⬜×7×4-140+140
1736=⬜×7×4
⬜=1736÷7÷4
⬜=62
Hope this helps you to understand better :) 