Unit 6 · Algebra
Magic Square — What Is the Missing ♦?
Lesson 20 of 24
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About this lesson
Row 1 gives magic total = 51. The anti-diagonal (top-right to bottom-left: 16, middle-centre, 18) gives middle-centre = 17. The main diagonal (20, 17, ♦) gives ♦ = 14.
Chapters
0:00Introduction
0:22The Question
0:52Determining the constant target sum
1:27Solving for the bottom-left corner continuity
1:58Utilising the diagonal path to isolate the diamond
2:26Executing the final calculation line
3:02Exam strategy — corner-to-opposite-centre balance
3:54Confirming the final option
Question
In a ‘magic square’, each row, each column and each diagonal add up to the same total.
In the magic square below, some of the numbers are missing.
What is the missing number at ♦?
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